Comparison of patterns of drug levels in head and body hair for medico-legal and workplace testing.

This paper presents concentration ranges and positivity rates for the common drugs, alcohol markers, new psychoactive substances (NPS) and anabolic steroids tested in head hair (n = 138,352) and body hair (n = 9532) on samples of hair from medico-legal (n = 112,033) and workplace (n = 35,851) sectors tested in our laboratory. Statistically significant higher levels were found more often in the various types of body hair when compared with head hair, but fewer cases exhibited lower levels. For example, statistically significant higher levels were detected in leg hair for cannabinol, THC, methadone and EtG and in beard hair for THC, THC-COOH and 6-acetylmorphine.

Testing venous carbohydrate-deficient transferrin or capillary phosphatidylethanol with concurrent ethyl glucuronide and ethyl palmitate hair tests to assess historical and recent alcohol use.

Hair biomarkers, ethyl glucuronide (EtG) and ethyl palmitate (EtPa), together with blood biomarker tests, carbohydrate-deficient transferrin (CDT) or phosphatidylethanol (PEth), are commonly used in identifying patterns of alcohol consumption as they possess different windows of detection. The detection of EtG in hair samples is mainly used in combination with EtPa when hair cosmetic treatments such as hair colouring and bleaching affect EtG levels. The main purpose of our study was to investigate the differences in frequency distribution of positive CDT and PEth results indicating alcohol had been used, when EtG and EtPa were not detected, where evidence of abstinence is paramount.

The Effect of Prolonged Storage Time on the Stability of Fatty Acid Ethyl Esters in Hair Samples.

The advantages of analysis of drugs in hair samples are recognized for the long window of detection, alongside easy sampling and long stability after sample collection. Alcohol markers, ethyl glucuronide (EtG) and total fatty acid ethyl esters (FAEEs) in hair, are widely used for monitoring alcohol consumption for clinical and forensic purposes. Although stability of drugs and EtG in hair samples is documented to a certain extent, stability of FAEEs in hair samples after collection has not been reported.

Adulterants in crack cocaine in Brazil.

Introduction: Brazil is the world's biggest consumer of crack cocaine, and dependence is a major public health issue. This is the first study to investigate the prevalence of potentially harmful adulterants present in hair samples from Brazilian patients with crack cocaine dependence.

Method: We evaluated adulterants in hair samples extracted by convenience from 100 patients admitted at the 48 hour-observation unit of Centro de Referência de Álcool, Tabaco e Outras Drogas (CRATOD), Brazil's largest center for addiction treatment.

Ethyl Glucuronide as a Long-term Alcohol Biomarker in Fingernail and Hair. Matrix Comparison and Evaluation of Gender Bias.

Aims: This work aimed to assess the performance of hair and fingernail ethyl glucuronide (EtG) measurement for use as a biomarker of alcohol consumption in persons with known drinking history across a range of drinking behaviours.

Methods: EtG concentrations were assessed from the hair and fingernails of 50 study participants. Alcohol consumption of the previous 90 days was assessed by participant interview using the alcohol timeline follow-back method.

Data on ethyl glucuronide and cocaethylene concentrations in the hair of cocaine users.

We present data on ethyl glucuronide and cocaethylene concentrations from the hair of cocaine users. Head hair from 64 subjects, previously tested for cocaine, cocaethylene, benzoylecogonine and anhydroecgonine methyl ester (AEME), were subsequently analysed for Ethyl Glucuronide (EtG). Samples were prepared by solid phase extraction and analysed using gas chromatrography coupled to tandem mass spectrometry.

Hair analysis when external contamination is in question: A review of practical approach for the interpretation of results.

Despite having been extensively discussed over the last decade, the differentiation between systemic exposure and external contamination still continues to be one of the limitations of hair testing for drugs. For this reason, we consider it worthwhile to re-state some basic principles in this short review. Various studies investigating a diversity of wash protocols, most using artificially contaminated hair with cocaine, have been valuable in evaluating wash efficacy and in understanding the incorporation of drugs in hair.

Commentary on current changes of the SoHT 2016 consensus on alcohol markers in hair and further background information.

The consensus on alcohol markers in hair was revised for the fourth time by an expert group of the Society of Hair Testing based on current state of research. This revision was adopted by the members of the Society during the business meeting in Brisbane on August 29th 2016. For both markers, ethyl glucuronide (EtG) and fatty acid ethyl esters (FAEEs), two cut-off values for discrimination between teetotalers or occasional low amount consumption and moderate alcohol drinking (low cut-off), and between non-excessive (abstinence up to moderate alcohol intake) and chronic excessive drinking (high cut-off value) were critically examined.

European guidelines for workplace drug and alcohol testing in hair.

Guidelines for Legally Defensible Workplace Drug Testing have been prepared and updated by the European Workplace Drug Testing Society (EWDTS). They are based on the 2010 version published by Pascal Kintz and Ronald Agius (Guidelines for European workplace drug and alcohol testing in hair. Drug Test.

Differentiation between consumption and external contamination when testing for cocaine and cannabis in hair samples.

It is possible for hair to be externally contaminated by drugs like cannabis or cocaine, which are smoked or snorted. Three steps are commonly employed to minimize the chance of external contamination causing misinterpretation of the results of a hair test. The first consists of decontamination of hair samples by washing the hair before analysis, the second is the use of cut-off levels, and the third is the detection of both the parent drugs and appropriate levels of their metabolite(s) in the hair sample.

Workplace drug testing, different matrices different objectives.

Drug testing is used by employers to detect drug use by employees or job candidates. It can identify recent use of alcohol, prescription drugs, and illicit drugs as a screening tool for potential health and safety and performance issues. Urine is the most commonly used sample for illicit drugs.

Simultaneous determination of GHB and EtG in hair using GCMS/MS.

A gas chromatographic tandem mass spectrometric (GCMS/MS) method for simultaneously determining trace concentrations of gamma-hydroxybutyrate (GHB) and ethyl glucuronide (EtG) in hair has been developed. Multiple reaction monitoring (MRM) was used to detect precursor and product ions of GHB, (233 and 147) and EtG (261 and 143) following anion exchange solid phase extraction and derivatization with N,O-bis[trimethylsilyl]trifluoroacetamide (BSTFA). Deuterated standards of GHB and EtG were used as internal standards.

Prevalence and disposition of drugs of abuse and opioid treatment drugs in oral fluid.

Testing oral fluid for drugs of abuse has been studied under many conditions but rarely has been evaluated in large population databases. We evaluated oral fluid tests in a database from a commercial laboratory in the United Kingdom composed of 8679 confirmed positive results. The results originated from 635,000 specimens collected over the period of May 2004 through September 2006.

Do drug users use less alcohol than non-drug users? A comparison of ethyl glucuronide concentrations in hair between the two groups in medico-legal cases.

Two groups were selected from the remainder of hair samples that had been tested for drugs at TrichoTech for medico-legal cases: samples that tested negative (drug-negative group; N=42, age 33.4+/-7.2 years) and samples that tested positive for drugs (drug-positive group; N=57, age 32.

Differentiation between drug use and environmental contamination when testing for drugs in hair.

The differentiation between systemic exposure and external contamination for certain drug groups has been frequently referred to as one of the limitations of in drug testing in hair. When hair samples are used, three steps are usually employed in order to minimise the possibility of external contamination causing a misinterpretation. The first consists of decontaminating hair samples by washing the hair before analysis, the second is the detection of the relevant metabolites in the hair samples and the third is the use of cut-off levels.

Patterns in drug use in the United Kingdom as revealed through analysis of hair in a large population sample.

This paper presents an overview of the most common sectioning patterns utilised in the analysis of hair for drug use; report on the major user groups (sectors) that currently make use of hair analysis in the United Kingdom (UK); present the results for the different drug groups analysed in samples of hair samples analysed at TrichoTech between 2001 and 2005. A total of 186,084 tests on 34,626 hair samples were performed for the commonly requested drug groups. There were 145,799 enzyme-linked Immunosorbent positive screening tests (ELISA), which were subsequently confirmed by gas chromatography equipped with mass spectrometry detection (GC-MS).

GC-MS-MS determination of gamma-hydroxybutyrate in blood and urine.

A gas chromatographic-tandem mass spectrometric (GC-MS-MS) method for determining trace concentrations of gamma-hydroxybutyrate (GHB) in blood and urine has been developed. Multiple reaction monitoring was used to detect parent and daughter ions of GHB, 233 and 147, respectively, following liquid-liquid extraction with acetonitrile and derivatisation with N,O-bis[trimethylsilyl]trifluoroacetamide (BSTFA). Deuterated GHB was used as an internal standard.

Gabapentin does not affect antipyrine clearance.

The effect of gabapentin on antipyrine clearance was assessed in 12 healthy male volunteers, using a known enzyme inducer, phenytoin, as control. Subjects received gabapentin 400 mg or phenytoin 100 mg three times daily for 2 weeks. Antipyrine tests were performed before, during, and after treatment with gabapentin or phenytoin.

Comparison by external quality assessment of performance of analytical systems for measurement of therapeutic drugs in serum.

The precision and accuracy of analytical methods currently in use for therapeutic drug monitoring were evaluated from proficiency test data provided by laboratories participating in the international Healthcontrol external quality assessment scheme for a range of eight antiepileptic drugs, theophylline, caffeine, and digoxin. Different analytical systems were assessed after grouping according to the reagent source and the analyzer used. The majority of analytical methods produced comparable levels of performance with coefficient of variation of < 10% and accuracy within +/-7% of the spike value.

External quality assessment of Syva Emit and Abbott TDx II assays for methotrexate in serum.

The Syva Emit and Abbott TDx II kits for determination of methotrexate in serum were compared using data from 14 samples distributed by the United Kingdom National External Quality Assessment Scheme to a mean of 38 European laboratories. For methotrexate concentrations above 0.2 mumol/L, there was no significant difference in the bias or coefficient of variation of measurements between the two techniques.

Time course of appearance of cotinine in human beard hair after a single dose of nicotine.

The time course of appearance of cotinine in saliva and in daily collections of beard clippings was monitored by gas chromatography with mass spectrometry in six volunteers who were nonsmokers following a single 30-min buccal administration of nicotine as a chewing gum. Salivary cotinine concentrations reached a plateau after 1.5 h and were nondetectable (< 0.

Phenobarbital in newborns with neonatal seizures. A study of plasma levels after intravenous administration.

Phenobarbital plasma levels were studied in a group of 25 newborn infants. Phenobarbital was administered i.v.

Intra- and interlaboratory sources of imprecision in drug measurements by different techniques.

We compared the intra- and interlaboratory precision of seven techniques used to measure eight antiepileptic drugs, digoxin, and theophylline by using data from the international Healthcontrol external quality-assessment scheme. Scheme participants were supplied blind with 6 or 12 sets of duplicate lyophilized serum samples. Each set contained different drug concentrations, and duplicates were analyzed separately, 1 to 6 months apart.

Performance of techniques for measurement of therapeutic drugs in serum. A comparison based on external quality assessment data.

Ten assay techniques were compared using measurements of a range of 15 drugs spiked in freeze-dried samples of serum reported to the Heathcontrol External Quality Assessment Scheme between November 1988 and January 1991. Three measures of performance were studied: frequency of outliers greater than 3 standard deviations from the sample mean, the coefficient of variation (CV) of sample measurements, and the difference of the sample mean from the spike value. The most consistently precise technique was polarisation fluoroimmunoassay (PFIA).

Cognitive functions of epileptic patients on monotherapy with phenobarbitone and healthy controls.

Quantitative measurements have indicated that heredity, cerebral damage, psycho-social aspects, ictal and inter-ictal phenomena and antiepileptic drugs may interfere in the cognitive dysfunction of epileptic patients. In the present study objective methods included immediate and late recall and recognition of pictures, Stroop test and auditory selection. Twenty patients with symptomatic localized epilepsy aged 17-52 years (27 +/- 10, mean +/- sd) were compared to age and socially matched healthy controls.