Gail Cooper

Society of Hair Testing guidelines for drug testing in hair

The Society of Hair Testing (SoHT) Guidelines for Drug Testing in Hair provide laboratories with recommended best practice guidelines whether they are currently offering drug testing in hair, or plan to offer a hair testing service in the future. The guidelines include reference to recommended sample collection and storage procedures, through sample preparation, pre-treatment and analysis and the use of cut-offs.

The United Kingdom and Ireland Association of Forensic Toxicologists: forensic toxicology laboratory guidelines (2010)

1. IntroductionThe UK and Ireland Association of Forensic Toxicologists (UKIAFT)consists of representatives from each of the main laboratories in theUnited Kingdom and Ireland offering Forensic Toxicology Services. Inthe absence of national guidelines for forensic toxicology, the UKIAFTapproached the board of the Society of Forensic Toxicologists (www.soft-tox.org) with a view to amending the Laboratory Guidelinespublished jointly by SOFT and the American Academy of ForensicSciences (AAFS). The SOFT/AAFS Forensic Toxicology Guidelines(Version 2006) were reviewed and amended to better reflecttoxicology standards and practices within the UK and Ireland.The UK and Ireland Association of Forensic Toxicologists ForensicToxicology Laboratory Guidelines (version 2010) acknowledge thefollowing international standards:• BS EN ISO/IEC 17025:2005 for testing laboratories and,• ILAC G-19 guidelines for forensic science laboratories.These guidelines do not necessarily reflect opinions about theminimum requirement for any laboratory, nor do they have anyregulatory purpose; rather, they are intended to assist laboratoriesengaged in the practice of forensic toxicology in achieving future goals.The UKIAFT acknowledge the substantive work carried out by theGuidelines Committee of SOFT and AAFS in establishing the SOFT/AAFS Forensic Toxicology Guidelines in 2006 which provided thisdocument (see Appendix 1).AlistoftheorganisationsfromtheUnitedKingdomandIrelandthathave contributed to the establishment of the UKIAFT ForensicToxicology Laboratory Guidelines is found in Appendix 2.2. ScopeThese guidelines are primarily for use in the practice of ForensicToxicology encompassing post-mortem forensic toxicology, humanperformance forensic toxicology and criminal forensic toxicology.There are separate guidelines available in relation to workplace drugtesting in the UK and Europe (www.ltg.uk.net and www.ewdts.org).3. DefinitionsForensic toxicology — determining the presence or sometimes theabsence of drugs and their metabolites, ethanol and other volatilesubstances, carbon monoxide and other gases, metals, hormones,biochemical metabolites resulting from in-born errors of metabolismand other toxic substances in human fluids and tissues.The function of this analysis can be as follows:Post-mortem toxicology — the determination of toxicologicalelements in death investigations.Human performance forensic toxicology — used to elucidate theabsence or presence of substances modifying human performanceor behaviour.Criminal toxicology — the determinants or toxicological factors intheinvestigationofcriminaloffences(forexamplemurder,allegedsexual assault and road traffic offences).Standard — a reference material containing target analyte(s)possessing one or more properties such as analyte concentration(s)thataresufficientlywellestablishedsothatitcanbeusedtopreparecalibrators.Calibrator — a solution containing target analyte(s), eitherprepared from the reference material or purchased, used tocalibratethe assay.Wherepossible,calibratorsshouldbepreparedin a matrix similar to that of the specimens to be analysed.Control — a solution containing target analyte(s) either preparedfrom the reference material (separately from the calibrators; thatis, weighed or measured separately), purchased, or obtained froma pool of previously analysed samples subject to ethical approvalandinaccordancewiththeHumanTissueAct.Controlsfromanyofthese sources are used to determine the validity of the calibration;that is, the stability of a quantitative determination over time.Where possible, controls should be matrix-matched to specimensand calibrators, as indicated above.Reference material (RM) — a material or substance containingtarget analyte(s), one or more properties of which, such as analyteconcentration(s) are established sufficiently well to be used forcalibration of an apparatus, assessing a measurement or assigningvalues to material (AOAC Official Methods of Analysis (1984)).

A study of methadone in fatalities in the Strathclyde Region, 1991-1996.

There was a substantial increase in the percent of drug screens testing positive for methadone between 1991 and 1996 in the Strathclyde region of Scotland. Seventy-nine per cent (n=136) of these deaths were drug-related, involving methadone either alone or in combination with other drugs such as diazepam, temazepam, alcohol and morphine. The involvement of methadone in the majority of these fatalities was due to diversion of legitimate supply. This paper highlights the dangers of resuming methadone consumption following a period of abstinence or when taken in combination with other drugs.

Comparison of GC-MS and EIA Results for the Analysis of Methadone in Oral Fluid

The purpose of these studies was to evaluate the performance characteristics of the Cozart Microplate Enzyme Immunoassay (EIA) for the determination of methadone in oral fluid from patients in a drug misuse treatment program. Oral fluid specimens were collected using the Cozart RapiScan Collection system from 198 donors who were receiving treatment for their addiction and were monitored for drug misuse. Oral fluid specimens were also collected from forty volunteer donors who were not drug users. The specimens were analyzed in the laboratory by EIA and then analysed for methadone and its main metabolite EDDP by gas chromatography-mass spectrometry (GC-MS). A total of 103 samples were confirmed positive for methadone. The Cozart Microplate EIA for d-Methadone in oral fluid using a cutoff of 30 ng/mL in diluted oral fluid had a sensitivity of 91.3% +/- 2.8% and a specificity of 100% +/- 1.0% vs. GC-MS.

Hair testing is taking root

An increasing number of toxicology laboratories are choosing to expand the services they offer to include hair testing in response to customer demands. Hair provides the toxicologist with many advantages over conventional matrices in that it is easy to collect, is a robust and stable matrix that does not require refrigeration, and most importantly, provides a historical profile of an individuals exposure to drugs or analytes of interest. The establishment of hair as a complementary technique in forensic toxicology is a direct result of the success of the matrix in medicolegal cases and the wide range of applications. However, before introducing hair testing, laboratories must consider what additional requirements they will need that extend beyond simply adapting methodologies already validated for blood or urine. Hair presents many challenges with respect to the lack of available quality control materials, extensive sample handling protocols and low drug concentrations requiring greater instrument sensitivity. Unfortunately, a common pitfall involves over-interpretation of the findings and must be avoided.

Guidelines for European workplace drug testing in oral fluid

Over the past decade, oral fluid has established itself as a robust testing matrix for monitoring drug use or misuse. Commercially available collection devices provide opportunities to collect and test oral fluid by the roadside and near-patient testing with both clinical and criminal justice applications. One of the main advantages of oral fluid relates to the collection of the matrix which is non-invasive, simple, and can be carried out under direct observation making it ideal for workplace drug testing. Laboratories offering legally defensible oral fluid workplace drug testing must adhere to national and international quality standards (ISO/IEC 17025); however, these standards do not address issues specific to oral fluid testing. The European Workplace Drug Testing Society (EWDTS) recognizes the importance of providing best practice guidelines to organizations offering testing and those choosing to use oral fluid drug testing to test their employees. The aim of this paper is to present the EWDTS guidelines for oral fluid workplace drug testing.

Sensitivity and Specificity of the Cozart Microplate EIA Cocaine Oral Fluid at Proposed Screening and Confirmation Cutoffs

BACKGROUND Oral fluid is currently being evaluated as an alternative matrix for monitoring illicit drugs in federally mandated workplace drug testing, for addiction treatment programs, and for driving under the influence testing. The sensitivity, specificity, and efficiency of the Cozart Microplate EIA Cocaine Oral Fluid Kit (COC ELISA) were determined by comparison with gas chromatography-mass spectrometry (GC/MS) results at screening and confirmation cutoffs proposed in the US and UK. METHOD Oral fluid was collected by expectoration after citric acid candy stimulation or with Salivette neutral cotton swabs or Salivette citric acid-treated cotton swabs before and after cocaine (COC) administration. Specimens (n = 1468) were analyzed with the COC ELISA for screening and with solid-phase extraction followed by GC/MS for confirmation. Three screening cutoffs (10, 20, and 30 microg/L) and four GC/MS cutoffs (2.5, 8, 10, and 15 microg/L COC, benzoylecgonine, and/or ecgonine methyl ester) were evaluated. GC/MS limit of quantification was 2.5 micro g/L for all analytes. RESULTS COC ELISA interassay imprecision (CV; n = 19) was 16% at 16.7 microg/L and 12% at 81.8 microg/L. With the 2.5, 8, 10, and 15 microg/L GC/MS cutoffs, 59.0%, 54.7%, 52.7%, and 48.7% of the oral fluid specimens were positive, respectively. Sensitivity, specificity, and efficiency were 92.2%, 84.7%, and 88.8%, respectively, for the suggested Substance Abuse and Mental Health Services Administration (SAMHSA) cutoffs and 90.2%, 89.2%, and 89.7% for cutoffs currently used in the UK. CONCLUSIONS COC ELISA had suitable sensitivity, specificity, and efficiency for identifying COC exposure at both the proposed SAMHSA and UK cutoffs. Sensitivity, specificity, and efficiency were >84% for both cutoffs, but 92 additional true-positive samples were identified with the SAMHSA cutoffs.

In utero drug and alcohol exposure in infants born to mothers prescribed maintenance methadone

Aims To describe the prevalence of in utero alcohol and illicit drug exposure in infants born to mothers prescribed methadone in pregnancy, and to compare the accuracy of maternal interview with infant toxicology. Methods Urine and meconium samples were collected from 56 infants born to mothers prescribed methadone during pregnancy and a confidential interview conducted soon after delivery. Samples were screened for drugs of misuse and meconium samples analysed for the presence of fatty acid ethyl esters (FAEEs) to detect prenatal alcohol exposure. Results 91% of infants had been exposed to illicit drugs in utero, including opiates (73%), benzodiazepines (70%) and cannabinoids (59%). 47% of infants had elevated FAEEs. Meconium was more sensitive at detecting in utero drug exposure than urine toxicology (p<0.01 for opiates, benzodiazepines, cannabinoids) or maternal interview (p=0.03 for opiates, p<0.01 for cannabinoids). Conclusions The majority of infants born to mothers prescribed methadone during pregnancy are exposed to polysubstance misuse, and almost one-half additionally exposed to excess alcohol.

Endogenous Concentrations of GHB in Postmortem Blood from Deaths Unrelated to GHB Use

Gamma-hydroxybutyrate (GHB) is an endogenous compound, but its presence in postmortem blood presents a challenge when interpreting elevated levels as GHB is misused as a recreational drug and is also produced postmortem. A total of 387 postmortem cases (273 male and 114 female) submitted to the toxicology laboratory between 2010 and 2012 specifically requested the analysis of the ketoacidosis biomarker, beta-hydroxybutyrate (BHB). No reference to GHB use was identified in any of the case files; however, BHB and GHB are measured simultaneously using deuterated GHB as the internal standard (GHB-d6) within a calibration range of 5-500 mg/L. GHB was not detected or <10 mg/L in 18% of the cases (n = 68), between 10 and 50 mg/L in 73% of the cases (n = 283) and between 51 and 193 mg/L in 9% of the cases (n = 36). The manner of death was classified as accidental (n = 11), alcohol-related (n = 237), drug-related (n = 23), homicide (n = 1), natural (n = 91), suicide (n = 9), medical-related (n = 1) and undetermined (n = 14). Six cases had GHB concentrations in excess of 100 mg/L with advanced decomposition changes noted in five of these cases. Moderate-to-advanced decomposition was also noted in 50% (n = 15) of the cases with GHB concentrations in excess of 50 mg/L but <100 mg/L. Approximately one-third of the blood samples tested contained a preservative and although a higher proportion of these samples had GHB concentrations <10 mg/L or not detected (∼30% preserved versus 11% unpreserved), there were still cases with GHB concentrations >51 mg/L (∼6% preserved versus 11% unpreserved). This study highlights the danger of only using a cutoff to establish endogenous levels compared with exogenous use of GHB in postmortem blood.

Determining the pattern and prevalence of alcohol consumption in pregnancy by measuring biomarkers in meconium

Objective To investigate the feasibility of determining the pattern and prevalence of alcohol consumption in pregnancy by measuring ethanol biomarkers in meconium. Design Population-based observational study. Setting Inner-city maternity unit in Scotland, UK. Population Random sample of singleton infants delivered after 36 completed weeks’ gestation. Methods Fatty acid ethyl esters (FAEEs) and ethyl glucuronide (EtG) in meconium were measured by liquid chromatography-mass spectroscopy. Samples were frozen at −20°C before analysis. Results were compared anonymously with demographic data including maternal age, parity, smoking, ethnicity and postcode and with infant gestation, birth weight and head circumference. Written informed consent was obtained from all subjects. Results 235 samples of meconium were analysed (70% of eligible babies). Only four (1%) of mothers declined to participate. FAAEs were detected in all, including four samples below the limit of quantification (10 ng/g). 98 (42%) samples had FAEE concentrations >600 ng/g. EtG was detectable in 93 (40%) samples; in 35 (15%) EtG concentration was >30 ng/g. No mother reported heavy alcohol consumption in pregnancy. FAAE concentration correlated with EtG (Pearson’s coefficient; p<0.001). There was no association between either biomarker and maternal age, parity, smoking, ethnicity or postcode, or infant gestation, birth weight or head circumference. Conclusion Measurement of ethanol biomarkers in meconium is a feasible tool for determining the pattern and prevalence of alcohol consumption in pregnancy. Data suggest that at least 15% of pregnant women in the west of Scotland are consuming significant quantities of alcohol during latter pregnancy.