Influence of bleaching and coloring on ethyl glucuronide content in human hair

Ethyl glucuronide (EtG) is increasingly used in forensic toxicology as a marker for alcohol use in analyses of hair samples, especially in abstinence control. Some cosmetic treatments are considered to markedly reduce the EtG content. In view of especially many women with coloured hair the present study was performed to further investigate the effect of a variety of colouring procedures (bleaching, tinting, permanent and semi‐permanent dyeing, henna) on the EtG content. Untreated hair samples (n = 12, EtG 13.9–64.7 pg/mg) were re‐analyzed (gas chromatography‐ negative chemical ionization mass spectrometry, 0.8 pg/mg quantification limit) after different treatment procedures. A decrease of the EtG content of at least 10% occurred in every case. The reduction in comparison to the untreated hair was expectedly high for permanent dyeing and bleaching with 18.1% of the initial content (median, range 0.0–50.9%) and 18.4% (0.0–46.7%), respectively. For henna this was 38.3% (0.0–83.0%), for tinting 70.4% (29.0–90.8%), for semi‐permanent dyeing 41.9% (0.0–77.4%). With permanent hair dye the EtG content was decreased to below 7 pg/mg in 10 of 12 cases, in 3 cases even below the LOD (0.2 pg/mg). Surprisingly henna treatment without oxidative component had a marked influence, EtG was below 2 pg/mg in 2 of 12 samples. The study showed that all tested coloration procedures markedly affected the deposited EtG content. Even temporary or henna coloration may have a marked effect. The present data support the recommendation to exclude hair samples with colour manipulations for analysis on the EtG content as a precaution in alcohol abstinence programs. Copyright © 2017 John Wiley & Sons, Ltd.     

Determination of 2,5-toluylenediamine (2,5-TDA) and aromatic amines in urine after personal application of hair dyes: kinetics and doses

The personal use of hair dye products is currently under discussion due to the potentially increased risk of bladder cancer among long-time users described in epidemiological literature. In order to investigate the dermal absorption of aromatic diamines as well as aromatic amines possibly present as contaminants in hair dye formulations, we conducted a biomonitoring study under real-life conditions and calculated kinetics and doses for the urinary excretion. Urine samples of two female subjects were collected for a time period of 48 h after personal application of a hair dye cream and analysed for aromatic diamines as well as o-toluidine and 4-aminobiphenyl using highly specific GC/MS-methods. 2,5-Toluylenediamine (2,5-TDA) as active ingredient of hair dyes is rapidly absorbed dermally. After a distribution phase of 12 h, 2,5-TDA is excreted with a half-time of 8 h. Excretion was 90% complete within 24 h after application. The doses of 2,5-TDA excreted within 48 h were 700 μg for application of a brown-reddish hair dye cream and 1.5 mg for the application of a brown-black hair dye cream. Urinary 4-aminobiphenyl as well as contaminations with other aromatic diamines were not detectable in our study. Due to the artifactual formation of o-toluidine in the presence of high concentrations of urinary 2,5-TDA, our results could not prove an increased internal exposure of humans to carcinogenic amines after personal application of hair dyes.     

Validation of the Cozart microplate ELISA for detection of opiates in hair

The purpose of this study was to determine the performance characteristics of the Cozart Opiates Microplate ELISA assay for the detection of opiates in hair specimens. One hundred and six hair specimens were collected from volunteers and from drug-related deaths. The hair samples were extracted by sonication followed by overnight extraction in methanol at 60 degrees C. The methanol extract was dried, reconstituted in ELISA negative calibrator, and then analyzed. For gas chromatography-mass spectrometry (GC-MS) analysis, deuterated internal standard mixture and 0.1M HCl were added to 20 mg of specimen or spiked blank hair and sonicated for 1 h. The opiates were extracted by solid-phase and derivatized with BSTFA + 1% TMS for GC-MS analysis. Fifty-one hair specimens were confirmed positive by GC-MS. The true positives, true negatives, false positives, and false negatives for different cutoffs with the ELISA were determined by comparison of the ELISA response (normalized to weight of hair extracted) to the GC-MS results as the reference method. The optimum cutoff for the Cozart Opiate Microplate ELISA was determined to be between 200 and 300 pg morphine equivalents/mg hair using a 20-mg hair sample. The Cozart Opiates Microplate EIA for opiates in hair using a cutoff of 200 pg/mg hair with a 20-mg hair sample had a sensitivity of 98% +/- 2% and a specificity of 92.7% +/- 3.5% versus GC-MS.     

Comparison of Cozart microplate ELISA and GC-MS detection of methadone and metabolites in human hair

The purpose of this study was to determine the performance characteristics of the Cozart Methadone Microplate ELISA assay for the detection of methadone and methadone metabolites in hair specimens. One hundred and ten hair specimens were collected from volunteers (n=46) with a history of drug use and from drug-related deaths (n=64). The hair samples (approximately 20 mg) were extracted by sonication in methanol followed by overnight extraction in methanol at 60 degrees C. The methanol extract was evaporated to dryness, reconstituted in ELISA negative calibrator, and then analyzed. For gas chromatography-mass spectrometry (GC-MS) analysis, deuterated internal standard mixture [methadone-d9 and 2-ethylidene-1,5-dimethyl-3,3-diphenylpyrrolidine (EDDP)-d3] and 0.1M HCI were added to approximately 20 mg of specimen or spiked blank hair and sonicated for 1 h. The pH was adjusted to neutral, and methadone and its primary metabolite, EDDP, were analyzed by GC-MS following solid-phase extraction using Bond Elute Certify columns and pH 7.4 phosphate buffer (0.1M). Forty hair specimens were confirmed positive for methadone by GC-MS. Concentrations ranged from 0.10 to 8.3 ng/mg for methadone and 0.1 to 1.2 ng/mg for EDDP. The true positives, true negatives, false positives, and false negatives for different cutoffs with the ELISA were determined by comparison of the ELISA response (normalized to weight of hair extracted) to the GC-MS results with a cutoff of 0.1 ng/mg for both methadone and EDDP as the reference method. The optimum cutoff for the Cozart Methadone Microplate ELISA was determined to be between 200 and 300 pg methadone equivalents/mg hair using a 20 mg hair sample. The Cozart Methadone Microplate EIA for methadone and metabolites in hair using a cut-off of 200 pg/mg hair with a 20 mg hair sample had a sensitivity of 95 +/- 2% and a specificity of 100 +/- 3.5% (vs GC-MS) and an accuracy of 98.2 +/- 1.3%.     

Assessment of PCBs exposure in human hair using double focusing high resolution mass spectrometry and single quadrupole mass spectrometry

Polychlorinated biphenyls (PCBs) levels were assessed in human hair samples, originating from two main agricultural regions of Greece. The analysis was performed by gas chromatography-mass spectrometry (GC-MS) and gas chromatography-double focusing high resolution mass spectrometry (GC-DFHRMS). The main analytical procedure involved hair decontamination, solid-liquid extraction and cleanup steps. The recoveries of PCBs ranged from 71.2% to 101.6%, with accuracies greater than 87.5% and the between-run precisions (%RSD) lower than 25% for all analytes. Differences in the frequencies of detection and the median values of PCBs were detected between the examined regions and between the applied analytical techniques. All Peloponnesus' hair examined samples were found positive for each examined PCB, while the percentage of the total positive samples ranged from 86.1% (for PCB 138) to 94.4% (for PCB 28 and 153 congeners) using GC-DFHRMS. The Cretan hair samples were less contaminated (SUM PCBs=0.61 and 1.47pg/mg) unlike the Peloponnesus' samples (SUM PCBs=24.68 and 38.74pg/mg) measured by GC-DFHRMS and GC-MS, respectively. PCBs with high chlorination gave lower concentration values compared to low chlorination PCBs in both populations. No significant differences were observed between women and men. The GC-DFHRMS technique provided higher percentage of positive samples and low PCBs median values, due to higher sensitivity and interferences from isobaric ions in the GC-MS technique and is therefore considered as a powerful tool for such assessments in hair specimens.     

Fully automated determination of cannabinoids in hair samples using headspace solid-phase microextraction and gas chromatography-mass spectrometry

This paper describes a fully automated procedure using alkaline hydrolysis and headspace solid-phase microextraction (HS-SPME) followed by on-fiber derivatization and gas chromatographic-mass spectrometric (GC-MS) detection of cannabinoids in human hair samples. Ten milligrams of hair was washed with deionized water, petroleum ether, and dichloromethane. After the addition of deuterated internal standards the sample was hydrolyzed with sodium hydroxide and directly submitted to HS-SPME. After absorption of analytes for an on-fiber derivatization procedure the fiber was directly placed into the headspace of a second vial containing N-methyl-N-trimethylsilyltrifluoroacetamide (MSTFA) before GC-MS analysis. The limit of detection was 0.05 ng/mg for delta9-tetrahydrocannabinol (THC), 0.08 ng/mg for cannabidiol (CBD), and 0.14 ng/mg for cannabinol (CBN). Absolute recoveries were in the range between 0.3 and 7.5%. Linearity was proved over a range from 0.1 to 20 ng/mg with coefficients of correlation from 0.998 to 0.999. Validation of the whole procedure revealed excellent results. In comparison with conventional methods of hair analysis this automated HS-SPME-GC-MS procedure is substantially faster. It is easy to perform without use of solvents and with minimal sample quantities, but with the same degree of sensitivity and reproducibility. The applicability was demonstrated by the analysis of 25 hair samples from several forensic cases. The following concentration ranges were determined: THC 0.29-2.20 (mean 1.7) ng/mg, CBN 0.55-4.54 (mean 1.2) ng/mg, and CBD 0.53-18.36 (mean 1.3) ng/mg. 11-nor-Delta9-tetrahydrocannabinol-9-carboxylic acid could not be detected with this method.     

Simultaneous determination of cannabidiol, cannabinol, and \gD9-tetrahydrocannabinol in human hair by gas chromatography-mass spectrometryin human hair by gas chromatography-mass spectrometry

An analytical method was developed for evaluating the cannabidiol (CBD), cannabinol (CBN), and delta9-tetrahydrocannabinol (delta9-THC) level in human hair using gas chromatography-mass spectrometry (GC-MS). Hair samples (50 mg) were washed with isopropyl alcohol and cut into small fragments (< 1 mm). After adding a deuterated internal standard, the hair samples were incubated in 1.0 M NaOH for 10 min at 95 degrees C. The analytes from the resulting hydrolyzed samples were extracted using a mixture of n-hexane-ethyl acetate (75:25, v/v). The extracts were then evaporated, derivatized, and injected into the GC-MS. The recovery ranges of CBD, CBN, and delta9-THC at three concentration levels were 37.9-94.5% with good correlation coefficients (r2 >0.9989). The intra-day precision and accuracy ranged from -9.4% to 17.7%, and the inter-day precision and accuracy ranged from -15.5% to 14.5%, respectively. The limits of detection (LOD) for CBD, CBN, and delta9-THC were 0.005, 0.002, and 0.006 ng/mg, respectively. The applicability of this method of analyzing the hair samples from cannabis abusers was demonstrated.     

GC-MS analysis of methamphetamine and amphetamine in hair of Thai drug addicts]

Psycho-stimulant dependence in young individuals has become a serious problem in Thailand, where consumption of the so-called YaBa methamphetamine tablets has become a fashionable trend. Due to its easy availability in the form of a tablet, young individuals abuse methamphetamine. Methamphetamine tablets are known to be potently addictive and its difficulty in cessation of drug use and to be abstinent from the drug. We herein report the results obtained from GC-MS analysis of methamphetamine and amphetamine in 33 samples of urine and hair from patients with psycho-stimulant dependence. These samples were collected from patients registered at the outpatient clinic in the Department of Psychiatry, Chiang Mai University Hospital and were sent to Nippon Medical School, Department of Legal Medicine (Tokyo, Japan) for further analysis by Dr. Werawan Ruangyttikarn, Department of Forensic Medicine, Chiang Mai University. Sample preparation: Hairs samples were cropped near the hair root. After washing, they were cut into 1.2-cm sections and extracted with methanol/5N HCl (2:1) for an hour and then, solid-phase extraction was conducted using Bond-Elut Certify. Following extraction, GC-MS analysis was performed. Urine samples were subjected to GC-MS analysis after preparation with Bond Elut Certify. Results and Discussion: In 6 samples, both urine and hair samples analyzed were negative for detection of the stimulant drugs. In those cases individuals might stop taking drug for about 5 months. In 18 samples, urine samples were negative whereas hair samples were positive. These results suggest that individuals might stop using drugs for a few days before they went to the hospital but they abuse drugs continuously. In 9 samples, both urine and hair samples were positive. These results show that individuals always abuse drugs. In order to treat drug dependence effectively it is necessary to obtain the patient history of drug use and to evaluate and determine short-term and long-term drug use with urinalysis and hair analysis, respectively. Our present data revealed that useful information concerned with the long term drug abuse can be obtained from hair analysis, and that this method of analysis is applicable not only to forensic cases but also for evaluating clinical cases.     

Determination of benzo[a]pyrene and other polycyclic aromatic hydrocarbons (PAHs) at trace levels in human tissues

A sensitive and rugged gas chromatographic-mass spectrometric (GC-MS) method was developed for determining 11 polycyclic aromatic hydrocarbons (PAHs) in 4-g specimens of human lung, breast, and liver tissue. The method quantitation limit (MQL) was 0.01-0.02 ng/g for benzo[a]pyrene (BaP) and six other five- and six-ring PAHs. The MQL was higher for four-ring PAHs because of their presence at trace levels in method blanks. The average MQLs for pyrene and chrysene were 0.05 and 0.03 ng/g, respectively. The method was applied to 200 human tissue specimens (89 lung, 68 breast, and 43 liver) obtained from patients during surgery. Quality-control results demonstrated average recoveries of 80% or better from reagent controls spiked at the 0.2-ng level and average recoveries from tissue fortified at the 0.25-ng/g level of 66-95%. The precision of the method was determined from duplicate analyses of specimens (16-38% RSD) and from duplicate GC-MS analysis of tissue extracts (8-17%RSD). Benzo[a]pyrene was detected at measurable levels in 87% of the lung specimens. This method makes possible the measurement of ambient levels of PAHs in small samples of human tissue such as those obtained by biopsy.     

Absorption of lawsone through human skin

Lawsone (2-hydroxy-1,4-naphthoquinone) is the principal color ingredient in henna, a color additive approved with limitations for coloring hair by the Food and Drug Administration (FDA) under 21 CFR 73.2190. In 2002, the scientific committee on cosmetics and non-food products (SCCNFP), now known as the scientific committee for consumer products (SCCP), evaluated the safety of lawsone as a coloring agent in hair dye products of the European Union (EU). The SCCNFP concluded that lawsone was mutagenic and not suitable for use as a hair coloring agent. As a result, studies were conducted to measure the extent of lawsone absorption through human skin. Lawsone skin absorption was determined from two hair coloring products and two shampoo products, all containing henna. [(14)C]-Lawsone (sp. act. 22.9 mCi/mmol) was added to each commercial product and the products were applied to dermatomed, nonviable human skin mounted in flow-through diffusion cells perfused with a physiological buffer (HEPES-buffered Hanks' balanced salt solution, pH 7.4). Products remained on the skin for 5 minutes (shampoos) and 1 hour (hair color paste). For the henna hair paste products, 0.3 and 1.3% of the applied dose was absorbed into the receptor fluid in 24 hours while 2.2 and 4.0% remained in the skin. For both henna shampoo products, 0.3% of the applied dose was absorbed into the receptor fluid at 24 hours while 3.6 and 6.8% remained in the skin. For all products, most of the lawsone applied was washed from the surface of the skin (83-102%) at the end of the exposure period. Extended absorption studies were conducted for 72 hours to determine if skin levels of lawsone in the 24 hour studies might eventually be percutaneously absorbed. These studies determined that the majority of the lawsone remained in the skin with only a small but significant increase (for three out of four products) in receptor fluid values. Therefore, it appears that receptor fluid values would give a good estimate of lawsone absorption for an exposure estimate and that skin levels of lawsone need not be included.     

Comparison of urine and hair testing for drugs of abuse in the control of abstinence in driver's license re-granting

The purpose of the study was to compare the detection rate of illicit drugs in urine and hair specimens. The samples were taken from subjects trying to regain their revoked driver's license after a drug- or alcohol-related traffic offence. In 2010, we screened 14 000 urine and 3900 hair samples for amphetamines, methamphetamines, cannabinoids, cocaine, opiates, methadone, and benzodiazepines as well as for ethylglucuronide. We used the low threshold values of the new German guidelines for Medical Psychological Assessment (MPA). Positive screening tests were confirmed with gas chromatography-mass spectrometry (GC-MS), gas chromatography-tandem mass spectrometry (GC-MS/MS) or liquid chromatography-tandem mass spectrometry (LC-MS/MS). The results show that positivity rates for methamphetamines, MDMA, cocaine, and monoacetylmorphine were 1.7-, 5.7-, 3.8- and 9.3-fold higher in hair than in urine. In contrast, the detection rate for benzodiazepines was higher in urine than in hair (oxazepam, 0.21% versus 0%, nordiazepam 0.10% versus 0.03%). The positivity rate in hair for ethylglucuronide was 6-fold (12.7%) that for urine testing (2.1%). The study reveals that in the control of abstinence in the context of driving license re-granting there are in part large differences of positivity rates for some drugs or metabolites between hair and urine samples. These differences should be kept in mind by physicians and psychologists in traffic medicine who are ordering the drug testing.     

Solid-phase microextraction for cannabinoids analysis in hair and its possible application to other drugs

This paper describes the application of solid-phase microextraction (SPME) to cannabis testing in hair. Fifty milligrams of hair was washed with petroleum ether, hydrolyzed with NaOH, neutralized, deuterated internal standard was added and directly submitted to SPME. The SPME was analyzed by GC-MS. The limit of detection was 0.1 ng/mg for cannabinol (CBN) and delta9-tetrahydrocannabinol (THC) and 0.2 ng/mg for cannabidiol (CBD). THC was detected in a range spanning from 0.1 to 0.7 ng/mg. CBD concentrations ranged from 0.7 to 14.1 ng/mg, and CBN concentrations ranged from 0.4 to 0.7 ng/mg. The effectiveness of different decontamination procedures was also studied on passively contaminated hair. The proposed method is also suitable for the analysis of methadone in hair; cocaine and cocaethylene can be detected in hair with SPME extraction after enzymatic hydrolysis.     

Comparative analysis of sweat patches for cocaine (and metabolites) by radioimmunoassay and gas chromatography-positive ion chemical ionization-mass spectrometry

Immunoassays are commonly used to screen samples prior to confirmation by gas chromatography-mass spectrometry (GC-MS). This serves two purposes: it provides a second method for positive samples, and it allows exclusion of negative samples from further confirmatory testing. In addition, immunoassay results can be used in some cases to determine if dilution of the sample will be required during the confirmatory assay. We used 878 sweat patches worn by 38 subjects receiving treatment for cocaine dependence to compare analysis of the extracts of the patches for cocaine immuno-equivalents by radioimmunoassay (RIA) with determination of cocaine, benzoylecgonine (BE), and ecgonine methyl ester (EME) by GC-MS. Preliminary validation experiments demonstrate that the GC-MS method using positive ion chemical ionization had sufficient specificity and recovery to support a lower limit of quantitation (LLOQ) of 4 ng/patch and was precise and accurate across a linear range up to 500 ng/patch. Cocaine ranging from the LLOQ to 31,900 ng/patch was found in 660 of the samples; BE ranging from the LLOQ to 3470 ng/patch was found in 530 of the samples; and EME ranging from the LLOQ to 2280 ng/patch was found in 476 of the samples. In a subset of 238 samples semiquantitative use of the RIA gave results that agreed with GC-MS with a correlation coefficient of 0.986, but averaged approximately 23% lower. Although this accuracy of the RIA supported its use as a sole quantitative assay, the limited linear range of the RIA (4-200 ng/patch) proved impractical for this purpose. Receiver operator characteristic analysis of the cutoffs of the RIA and GC-MS suggested optimal cutoffs of 5 and 4 ng/patch, respectively. At these cutoffs, the RIA had sensitivity of 90.0% and specificity of 92.2%. For samples that had RIA results greater than the high calibrator (N = 228), various dilution schemes were assessed for their ability to predict retention of either cocaine alone or cocaine and both metabolites within the linear range of the GC-MS. When cocaine was the only analyte of interest, a single 20-fold dilution retained 200 (87.7%) of the samples. This compared to an optimal scheme where a different dilution was selected for each one-tenth ratio (< 0.1, 0.1-0.2, etc.) where 211 (92.5%) of the samples were retained. When trying to retain cocaine and both metabolites, dilution schemes were less successful as BE and EME would often fall below the LLOQ of the GC-MS. A single fivefold dilution of all samples retained 115 (50.4%) compared to an optimum of 143 (62.7%). The optimum could be approached with four dilution sets retaining 142 of the samples. Time expended on performing RIA analysis of all the samples was cost-effective when the results were used to exclude negatives from and predict dilutions required for GC-MS analysis. RIA offers a cost-effective, sensitive, and specific alternative initial test for cocaine determination in extracts of sweat patches.     

PTCA (1H‐pyrrole‐2,3,5‐tricarboxylic acid) as a marker for oxidative hair treatment

Hair analysis for the assessment of alcohol or drug abstinence has become a routine procedure in forensic toxicology. Hair coloration leading to loss of incorporated xenobiotics and to false negative results has turned out to be a major problem. Currently only colored extracts provide hints of manipulations but not bleaching. A liquid chromatographic–tandem mass spectrometric (LC–MS/MS) method was developed and validated to determine 1H‐pyrrole‐2,3,5‐tricarboxylic acid (PTCA), a major oxidation product of melanin. PTCA was determined in natural hair samples (n = 21) after treatment with 3% hydrogen peroxide (H₂O₂) for 30 or 40 minutes with concentrations up to 12% for 40 minutes. In another series, 12 natural hair samples were submitted to different coloration procedures (henna, tinting, semi‐permanent and permanent dyeing, bleaching) and the changes in PTCA content were determined. A significant increase in the PTCA content was found for both incubation times and increasing H₂O₂ concentrations. Coloration with henna or tinting had no influence on PTCA levels detected, but a significant increase was observed after semi‐permanent and permanent dyeing and bleaching. As PTCA concentrations in natural hair were found to be in a range of <2.1–16.4 ng/mg (8.4 ± 3.8 ng/mg, mean ± SD, n = 33), a cut‐off of 20 ng/mg is recommended for the distinction between natural vs. excessively oxidized hair. In case of naturally low melanin content (light‐blond or white hair), no marked increase in PTCA may occur. The present study demonstrated that PTCA is formed during oxidative treatment of melanin in hair, which can be used to detect previous hair coloration including oxidation.     

Validation of the immunalysis microplate ELISA for the detection of methamphetamine in hair

The object of this study was to validate the Immunalysis Methamphetamine Microplate ELISA for detecting methamphetamine in hair. Twenty-nine scalp hair samples were obtained as routine cases submitted to the National Institute of Scientific Investigation in Seoul by the police. The hair samples were washed with 0.1% sodium dodecyl sulfate, distilled water, and dichloromethane. The samples were screened using the Immunalysis Methamphetamine Microplate ELISA and confirmed using gas chromatography-mass spectrometry (GC-MS). Twenty-eight hair samples were screened and confirmed as positive for methamphetamine. For ELISA analysis, the samples were extracted by incubation in monobasic phosphate buffer for 1 h at 60 degrees C. For GC-MS, the samples were extracted for 20 h in methanol containing 1% hydrochloric acid. The methanol/acid solution was evaporated to dryness and the resulting residue was derivatized with trifluoroacetic anhydride. Methamphetamine and amphetamine were detected using selective ion monitoring (SIM) mode. The Immunalysis Methamphetamine Microplate ELISA demonstrated a sensitivity and specificity of 97% and 100%, respectively, using a cut-off concentration of 0.5 ng/mg d-methamphetamine. The ELISA kit showed 63% cross-reactivity with d,l-methamphetamine and did not cross-react to any significant extent with the licit l-methamphetamine isomer. The intra- and interassay precisions were 2.5% and 3.7%, respectively.     

Determination of GHB in human hair by HPLC‐MS/MS: Development and validation of a method and application to a study group and three possible single exposure cases

Gamma‐hydroxybutyrate (GHB) over the last two decades has generated increased notoriety as a euphoric and disinhibiting drug of abuse in cases of drug‐related sexual assault and for this reason it is considered a ‘date rape’ drug. The first aim of this paper was to develop and fully validate a method for the detection of GHB in human hair by high performance liquid chromatography‐tandem mass spectrometry (HPLC‐MS/MS) after liquid‐liquid extraction (LLE). The second aim was the application of the method to hair samples of 30 GHB‐free users in order to determine the basal level. The results obtained showed no significant differences in endogenous concentrations (p = 0.556) between hair samples of the three groups (black, blonde, and dyed hair) and the age and sex of the subjects did not affect the endogenous levels. Another 12 healthy volunteers, with no previous history of GHB use, were selected and a single dose (25 mg/Kg) was orally administered to all of them and hair samples were collected before the administration of the single dose and other two samples were collected one month and two months later, respectively. The segmental analysis of the latter two samples allowed us to calculate two ratios: 4.45:1 (95% C.I. 3.52–5.63) and 3.35:1 (95% C.I. 2.14–5.18), respectively, which can be recommended as reasonable values for a positive identification of GHB intake. Finally the method was applied to three real cases where a GHB single exposure probably occurred. Copyright © 2014 John Wiley & Sons, Ltd.     

Preparation and evaluation of semi-permanent hair dyes liposome

This study used phospholipids from fresh egg yolks to prepare liposome-encapsulated semi-permanent hair dyes in different pH buffer solutions and evaluated the functions and colour fastness to washing of the dyes. The extraction ratio of egg yolk phospholipids was 5%, and the purity was 91.8%. Empty liposome solutions were then prepared using high-speed homogenizer with particle size 219-848?nm. After being stored at 4 °C for 28 days, the average particle size of the liposome-encapsulated dye formulas increased from 1.36-1.92?μm to 1.99-2.38?μm. The ΔE colour difference values of the five hair extension sets dyed with the control group and hair dyes on the market were of the range 6.56-13.39 after eight times of washing, whereas the ΔE values of the four hair extension sets dyed with the liposome-encapsulated dyes were of the range 3.56-5.21 after eight times of washing. The liposome-encapsulated dye at pH 3 showed the best result.     

Validation of a gas chromatography--ion trap tandem mass spectrometry for simultaneous analyse of cocaine and its metabolites in saliva

Cocaine (COC) is one of the most widely used drugs of abuse. Therefore numerous procedures are published in the literature to propose an analysis of this substance and related compounds in different matrixes. In the same way, the authors have described, in a previous work, the simultaneous analysis of COC and three of its metabolites in hair by gas chromatography-ion-trap tandem mass spectrometry (GC-MS/MS) using chemical ionization with isobutane. The present paper investigated the ability to transfer this convenient existing method for hair to another matrix, in occurrence saliva. The aim of this work was then to verify that the whole procedure (solid phase extraction (SPE) and analytical method) was also convenient to analyse simultaneously COC and three of its metabolites in this matrix. Therefore this sensitive GC-MS/MS method has been studied for the simultaneous analysis of COC, anhydroecgonine methylester (AEME), ecgonine methylester (EME) and cocaethylene (COET) in saliva samples. The method has been validated and its performances were evaluated in terms of trueness and precision using quality control (QC) samples. For quantification, the following ranges were found appropriate: 5-500 ng/ml for EME, 2-500 ng/ml for COC and COET; AEME could only be determined "semi-quantitatively" between 2 and 200 ng/ml according to our chosen acceptance criteria. Suggested dissociation pathways have also been proposed to interpret the obtained spectra.     

Re-using henna natural dyeing wastewater for coloration and multifunctional finishing of linen fabric

Owing to their renewability and environmental friendly nature, natural dyes have been widely investigated in the textile sector over the past few decades. Natural dyeing technology, however, generally require toxic metal salt mordants to improve fastness and other functional properties; a large amount of mordants are unfixed and are discarded into wastewaters which represent dramatic environmental problems. The present work represents a cleaner production strategy by reusing wastewater of henna dyebath for the development of functional and coloured linen fabrics. The reuse of dyeing liquor was done in a systematic way and the dyed linen was characterized by several spectroscopic techniques. The analysed colour measurements, UV protection, and antioxidant property of dyed linen were very good. The obtained data in terms of chemical oxygen demand, TDS, conductivity, redox potential and pH of the bath showed that almost zero percentage of mordant salt remains in exhaust bath after three successive dyeing.     

The debate on carcinogenicity of permanent hair dyes: new insights

Oxidative (permanent) hair dyes contain one or several "primary intermediates" (e.g., p-phenylenediamines, p-aminophenols) and "couplers" (e.g., m-aminophenols, m-hydroxyphenols). In the presence of peroxide, the primary intermediate(s) and the coupler(s) undergo a chemical reaction to form colored oligomers. In the 1970s a number of aromatic amines used in oxidative hair dyes were identified as mutagenic and/or carcinogenic in rodents after lifetime oral administration. In response, regulatory action was taken, and some hair dye ingredients were banned in the European Union. Although recent results suggest that the main "primary intermediate" of oxidative hair dyes, p-phenylenediamine, has a weak genotoxic potential in vitro, it was not mutagenic in a mixture with nonmutagenic couplers, if tested under conditions comparable to those of practical use. Under conditions of use of permanent hair dyes, between 0.1 and 0.5% of the applied p-phenylenediamine may be absorbed through the skin. Acetylation in the skin is a key metabolic step for the primary intermediates p-phenylenediamine and p-aminophenol. Because of the involvement of aromatic amines, the discussion on the carcinogenicity of hair dyes in humans has been focused on urothelial cancer. Numerous epidemiological studies have investigated the risk of bladder cancer associated with the profession as a hairdresser, as well as the risk to consumers of hair dyes. Although some earlier studies suggested an overrepresentation of bladder cancer in male hairdressers, the majority of modern studies do not show an increase in relevant bladder cancer risk for professional or personal use of oxidative hair dyes. Today, there seems to be no relevant bladder cancer risk from the use of oxidative hair dyes. Such a conclusion can be derived from new toxicokinetic and metabolism investigations and is in general accordance with current epidemiological data. Human urothelial cancers, chemically induced by aromatic amines, have typical latency times often longer than 20 years. Since earlier exposures could have an impact decades later, the possibility of bladder cancer in hairdressers having intensively worked with permanent hair dyes during earlier decades (prior to the 1980s) should be taken into account.