Journal of analytical toxicology (J ANAL TOXICOL )

Description

Journal of Analytical Toxicology (JAT) is the international source for practical clinical/forensic applications for isolating, identifying and quantitating potentially toxic substances. The Journal of Analytical Toxicology (JAT) is an international publication devoted to the timely dissemination of scientific communications concerning the isolation, identification, and quantitation of drugs and other substances. Since its inception in 1977, JAT has striven to present state-of-the art techniques to address current issues in toxicology. The peer-review process provided by the distinguished members of the Editorial Advisory Board ensures the high quality and integrity of JAT articles. Timely presentation of the latest scientific developments is ensured through "Technical Notes", "Case Reports", and "Letters to the Editor". Worldwide readership of JAT includes toxicologists, pathologists, chemists, clinicians, researchers, and educators working in medical examiner and law enforcement laboratories, hospitals, university, and independent analytical laboratories, as well as the drug manufacturing industry. With an emphasis on practical application, JAT articles introduce improved and novel techniques for use in clinical, forensic, workplace, sports testing (doping), and other toxicology laboratories. Articles describe newly developed methods in immunoassay testing, gas chromatography, liquid chromatography, mass spectrometry, atomic absorption spectrometry, solid- and liquid-phase extraction techniques, and other analytical approaches. The methods published in JAT describe the chemical analysis of therapeutic drugs, drugs of abuse, pharmaceuticals, pesticides, industrial chemicals, and environmental toxins. The methods are generally applicable to the fields of forensic science, therapeutic drug monitoring, drug abuse testing, clinical and forensic toxicology, industrial hygiene.

Impact factor 2.63

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    Impact factor
  • 5-year impact
    1.76
  • Cited half-life
    8.60
  • Immediacy index
    0.43
  • Eigenfactor
    0.00
  • Article influence
    0.47
  • Website
    Journal of Analytical Toxicology (JAT) website
  • Other titles
    Journal of analytical toxicology, JAT
  • ISSN
    1945-2403
  • OCLC
    2942106
  • Material type
    Periodical
  • Document type
    Journal / Magazine / Newspaper

Publications in this journal

  • [Show abstract] [Hide abstract]
    ABSTRACT: A rapid, highly sensitive and specific analytical method for the extraction, identification and quantification of nine rodenticides from whole blood has been developed and validated. Commercially available rodenticides in Australia include coumatetralyl, warfarin, brodifacoum, bromadiolone, difenacoum, flocoumafen, difethialone, diphacinone and chlorophacinone. A Waters ACQUITY UPLC TQD system operating in multiple reaction monitoring mode was used to conduct the analysis. Two different ionization techniques, ES+ and ES-, were examined to achieve optimal sensitivity and selectivity resulting in detection by MS-MS using electrospray ionization in positive mode for difenacoum and brodifacoum and in negative mode for all other analytes. All analytes were extracted from 200 µL of whole blood with ethylacetate and separated on a Waters ACQUITY UPLC BEH-C18 column using gradient elution. Ammonium acetate (10 mM, pH 7.5) and methanol were used as mobile phases with a total run time of 8 min. Recoveries were between 70 and 105% with limits of detection ranging from 0.5 to 1 ng/mL. The limit of quantitation was 2 ng/mL for all analytes. Calibration curves were linear within the range 2-200 ng/mL for all analytes with the coefficient of determination ≥0.98. The application of the proposed method using liquid-liquid extraction in a series of clinical investigations and forensic toxicological analyses was successful. © The Author 2015. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.
    Journal of analytical toxicology 01/2015;
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    ABSTRACT: Oxycodone (OC) is recommended to be included as an analyte tested in the proposed Substance Abuse and Mental Health Services Administration (SAMHSA's) Mandatory Guidelines for Federal Workplace Drug Testing Programs using Oral Fluid (OF) Specimens. This study demonstrates the time course of OC and metabolites, noroxycodone (NOC), oxymorphone (OM) and noroxymorphone (NOM), in near-simultaneous paired OF and whole blood (BL) specimens by liquid chromatography-tandem mass spectrometry (LC-MS-MS) (limit of detection = 1 ng/mL OF, 5 ng/mL BL). A single dose of OC 20 mg controlled-release was administered to 12 healthy subjects followed by specimen collections for 52 h. Analyte prevalence was as follows: OF, OC > NOC > OM; and BL, OC > NOC > NOM. OC and NOC were frequently detected within 15-30 min in OF and 30 min to 2 h in BL. NOM and OM appeared between 1.5-5 h post-dose. The mean OF-to-BL (OF:BL) ratios and correlations were 5.4 for OC (r = 0.719) and 1.0 for NOC (r = 0.651). The period of detection for OF exceeded BL by ∼2-fold at similar cutoff concentrations. At a 1 ng/mL cutoff for OF, the mean detection time was 34 h for OC and NOC. These data provide new information that should facilitate interpretation of OC test results. © The Author 2015. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.
    Journal of analytical toxicology 01/2015;
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    ABSTRACT: In this study, an incubation, solid-phase extraction (SPE) and LC-MS-MS procedure was developed, validated and used for simultaneous analysis of amphetamine (AP), methamphetamine (MA), morphine (MOR), codeine (COD), 6-acetylmorphine (6-AM) and 6-acetylcodeine (6-AC) in hair. Hair samples were initially cut into sections, washed with dichloromethane, then sonicated in a methanol-trifluoroacetic acid mixture. The resulting solutions were processed with a SPE procedure before undergoing LC-MS-MS analysis. Mass spectrometric analysis was performed in positive-ion, multiple reactions monitoring (MRM) mode, using appropriate collision energy for each selected precursor ion. The overall protocol, when applied to the analysis of hair (50 mg) samples fortified with 100-10,000 pg/mg of the analytes, was found to achieve 55.5-74.6% recovery of the six analytes with the following analytical parameters: (i) intra- and interday precision/accuracy data for the six analytes in the 1.6-7.6%/-6.0-12.8% and 1.3-6.6%/-6.9-9.3% ranges, respectively; (ii) r(2) > 0.998 for all six analytes and (iii) LOD 2 pg/mg for AP and MA, and 8 pg/mg for MOR, COD, 6-AM and 6-AC; LOQ 10 pg/mg for all six analytes. This method was then utilized to (i) analyze hair samples collected from 86 self-reported drug users and (ii) evaluate the deposition pattern of drugs in head hairs from four female MA and heroin users in a rehabilitation facility. This relatively simple protocol was found superior over the GC-MS methods we have previously developed and utilized in our laboratory for the analysis of these six analytes. © The Author 2015. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.
    Journal of analytical toxicology 01/2015;
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    ABSTRACT: The toxicodynamics and, to a lesser degree, toxicokinetics of the widely used opiate codeine remain a matter of controversy. To address this issue, analytical methods capable of providing reliable quantification of codeine metabolites alongside codeine concentrations are required. This article presents a validated method for simultaneous determination of codeine, codeine metabolites codeine-6-glucuronide (C6G), norcodeine and morphine, and morphine metabolites morphine-3-glucuronide (M3G) and morphine-6-glucuronide (M6G) in post-mortem whole blood, vitreous fluid, muscle, fat and brain tissue by high-performance liquid chromatography mass spectrometry. Samples were prepared by solid-phase extraction. The validated ranges were 1.5-300 ng/mL for codeine, norcodeine and morphine, and 23-4,600 ng/mL for C6G, M3G and M6G, with exceptions for norcodeine in muscle (3-300 ng/mL), morphine in muscle, fat and brain (3-300 ng/mL) and M6G in fat (46-4,600 ng/mL). Within-run and between-run accuracy (88.1-114.1%) and precision (CV 0.6-12.7%), matrix effects (CV 0.3-13.5%) and recovery (57.8-94.1%) were validated at two concentration levels; 3 and 150 ng/mL for codeine, norcodeine and morphine, and 46 and 2,300 ng/mL for C6G, M3G and M6G. Freeze-thaw and long-term stability (6 months at -80°C) was assessed, showing no significant changes in analyte concentrations (-12 to +8%). The method was applied in two authentic forensic autopsy cases implicating codeine in both therapeutic and presumably lethal concentration levels. © The Author 2015. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.
    Journal of analytical toxicology 01/2015;
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    ABSTRACT: An analytical method was developed and validated for the purpose of detecting and quantifying 37 new designer drugs including cathinones, hallucinogenic phenethylamines and piperazines. Using only 100 µL whole blood, a salting-out-assisted liquid-liquid extraction with acetonitrile was performed to isolate target compounds followed by chromatographic separation using a Waters ACQUITY ultra performance liquid chromatograph coupled to a Waters XEVO quadrupole time-of-flight mass spectrometer. Mephedrone-d3 was used as an internal standard. A gradient elution was used in combination with a Waters ACQUITY HSS C18 column (2.1 × 150 mm, 1.8 µm). Samples were analyzed using the detector in positive electrospray ionization mode with MS(E) acquisition. All compounds of interest were resolved in a 15 min run time and positively identified based on accurate mass of the molecular ion, two product ions and retention time. All analyte calibration curves were linear over the range of 0.05-2 mg/L with most correlation coefficient (r(2)) values >0.98. The limits of detection were within the range of 0.007-0.07 mg/L and limits of quantification within 0.05-0.1 mg/L. All analytes were stable 48 h after extraction and most were stable in blood after 1 week stored in a refrigerator and 3 freeze-thaw cycles. No carryover was observed up to 10 mg/L and no interferences from common therapeutic drugs or endogenous compounds. Recoveries ranged from 71 to 100% and matrix effects were assessed for blank, post-mortem and decomposed blood. All bias and % coefficient of variation values were within the acceptable values of ±15 and ≤15%, respectively (±20 and ≤20% at lower limit of quantification). The method was applied to several forensic cases where the subject exhibited behavior characteristic of designer drug intoxication and where routine screening for a panel of drugs was negative. © The Author 2014. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.
    Journal of analytical toxicology 12/2014;
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    ABSTRACT: During a cross-validation practice of urinary analysis of pyrethroid insecticide metabolite (3-phenoxybenzoic acid, 3-PBA) by two laboratories (Lab A and Lab B), difference in 3-PBA concentration was noticed. The analytical methods used in the exercise were enzymatic deconjugation (glucuronidase/sulfatase) followed by solid phase extraction and isotope dilution LC-MS-MS determination (Lab A) and acidic deconjugation followed by liquid-liquid extraction and gas chromatography-mass spectrometry determination (Lab B). A significant difference was found for one of the five samples: lower value was obtained in Lab A. Use of acidic deconjugation in Lab A resulted in comparable value with the analytical result for this sample originally obtained in Lab B. The comparison was extended to 42 urine samples taken from Japanese males in Lab A by using the two different deconjugation methods and LC-MS-MS determination. Significantly lower value was obtained for enzymatic deconjugation in some of the 42 urine samples. The results suggested the presence of other conjugated species of 3-PBA than glucuronide and sulfate in human urine. Although the overall agreement between the values obtained by the deconjugation methods was fair, it appears that urine samples should be pretreated by acidic deconjugation for the analysis in biological monitoring of pyrethroid exposure. © The Author 2014. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.
    Journal of analytical toxicology 12/2014;
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    ABSTRACT: The misuse of β-agonists constitutes a potential risk to public health and has been forbidden in many countries. In this study, we describe a method for specific, sensitive and rapid detection of β-agonists in human urine. Urine samples were extracted with ethyl acetate, without any additional purification step, and analyzed by ultra-performance liquid chromatography-tandem mass spectrometry (UPLC-MS-MS) with Clenbuterol-D9 and Salbuterol-D3 as internal standards. The intra- and interday precision values of the method were all <5.60% and the accuracy ranged from 94.5 to 109%. Extraction recovery for 11 β-agonists varied from 66.7 to 108%. One UPLC-MS-MS analysis could be completed within 12 min and the limits of detection for 11 β-agonists were 0.1 ng/mL in the experiment. β-Agonists in human urines from 24 volunteers were analyzed by our validated method and 1.70 ng/mL salbutamol was detected in one volunteer. The application of UPLC-MS-MS method in β-agonists detection of human urine will be helpful in veterinary control of β-agonists and for studying the effect of β-agonists on human health. © The Author 2014. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.
    Journal of analytical toxicology 12/2014;
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    ABSTRACT: A method for the simultaneous extraction of the hallucinogens psilocin, bufotenine, lysergic acid diethylamide (LSD) as well as iso-LSD, nor-LSD and O-H-LSD from hair with hydrochloride acid and methanol is presented. Clean-up of the hair extracts is performed with solid phase extraction using a mixed-mode cation exchanger. Extracts are measured with liquid chromatography coupled with electrospray tandem mass spectrometry. The method was successfully validated according to the guidelines of the 'Society of Toxicological and Forensic Chemistry' (GTFCh). To obtain reference material hair was soaked in a solution of the analytes in dimethyl sulfoxide/methanol to allow incorporation into the hair. These fortified hair samples were used for method development and can be employed as quality controls. © The Author 2014. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.
    Journal of analytical toxicology 12/2014;
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    ABSTRACT: A 30-year-old man reportedly ingested pills and used illicit drugs with another person. They both fell asleep that night and the following afternoon the other person found him dead. There were used hypodermic needles and a metal spoon with dark tarry substance at the death scene, and two recent puncture sites were found on his body. It was uncertain if he had a history of illicit drug use. Postmortem blood initially screened borderline positive for methamphetamine by ELISA. An alkaline drug screen-detected ethylone which was subsequently confirmed and quantified by a specific GC-MS SIM analysis following solid-phase extraction. Concentrations were determined in the peripheral blood (0.39 mg/L), central blood (0.38 mg/L), liver (1.4 mg/kg), vitreous (0.58 mg/L), urine (20 mg/L) and gastric contents (12 mg). Other compounds detected in peripheral blood were morphine (0.05 mg/L), alprazolam (<0.05 mg/L), delta-9-THC (<1 ng/mL), delta-9-carboxy-THC (3.6 ng/mL) and naproxen (<5 mg/L). A urine screen (GC-MS) also confirmed 6-monoacetylmorphine, codeine and sildenafil. The cause of death was certified due to mixed ethylone, heroin and alprazolam intoxication. The manner of death was certified as accident. © The Author 2014. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.
    Journal of analytical toxicology 12/2014;
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    ABSTRACT: A 24-year-old man whose medical history was significant for alcohol abuse and depression was found unresponsive in bed. He had several prior suicide attempts with 'pills' and had also been hospitalized for an accidental overdose on a previous occasion. Autopsy findings were unremarkable apart from pulmonary edema and congestion, and urinary retention. Postmortem peripheral blood initially screened positive for mitragynine 'Kratom' (by routine alkaline drug screen by gas chromatography-mass spectrometry, GC-MS), which was subsequently confirmed by a specific GC-MS selective ion mode analysis following solid-phase extraction. Concentrations were determined in the peripheral blood (0.23 mg/L), central blood (0.19 mg/L), liver (0.43 mg/kg), vitreous (<0.05 mg/L), urine (0.37 mg/L) and was not detected in the gastric. Therapeutic concentrations of venlafaxine, diphenhydramine and mirtazapine were also detected together with a negligible ethanol of 0.02% (w/v). The results are discussed in relation to previous cases of toxicity, and the lack of potential for mitragynine postmortem redistribution. © The Author 2014. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.
    Journal of analytical toxicology 12/2014;
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    ABSTRACT: Organophosphate nerve agents (OPNAs) are some of the most widely used and proliferated chemical warfare agents. As evidenced by recent events in Syria, these compounds remain a serious military and terrorist threat to human health because of their toxicity and the ease with which they can be used, produced and stored. There are over 2,000 known, scheduled compounds derived from common parent structures with many more possible. To address medical, forensic, attribution, remediation and other requirements, laboratory systems have been established to provide the capability to analyze 'unknown' samples for the presence of these compounds. Liquid chromatography/mass spectrometric methods have been validated and are routinely used in the analysis of samples for a very limited number of these compounds, but limited data exist characterizing the electrospray ionization (ESI) and mass spectrometric fragmentation pathways of the compound families. This report describes results from direct infusion ESI/MS, ESI/MS(2) and ESI/MS(3) analysis of 14 G and V agents, the major OPNA families, using an AB Sciex 4000 QTrap. Using a range of conditions, spectra were acquired and characteristic fragments identified. The results demonstrated that the reproducible and predictable fragmentation of these compounds by ESI/MS, ESI/MS(2) and ESI/MS(3) can be used to describe systematic fragmentation pathways specific to compound structural class. These fragmentation pathways, in turn, may be useful as a predictive tool in the analysis of samples by screening and confirmatory laboratories to identify related compounds for which authentic standards are not readily available. Published by Oxford University Press 2014. This work is written by (a) US Government employee(s) and is in the public domain in the US.
    Journal of analytical toxicology 12/2014;
  • Journal of analytical toxicology 12/2014;
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    ABSTRACT: Urine and plasma specimens fortified with 82 drugs and metabolites were prepared and analyzed by liquid chromatography quadrupole time-of-flight mass spectrometry (QTOF) instrumentation from three different vendors using the instrument manufacturers' methods and workflows for drug screening. No prior knowledge about the compounds included or their concentrations were provided. Samples were prepared and sent for analysis on a TripleTOF(®) 5600 system, a 6530 QTOF and a Xevo(®) G2-S QTof. All three platforms performed well with >90% of compounds detected in one set of spiked plasma samples, and 79-88% for a second set of spiked plasma and two sets of spiked urine samples. © The Author 2014. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.
    Journal of analytical toxicology 12/2014;
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    ABSTRACT: Clenbuterol (CLE) is used in horses as a bronchodilator and for its anabolic steroid-like effects. CLE is a Class 3 drug according to current Association of Racing Commissioners International (ARCI) Uniform Classification Guidelines. The Racing Medication and Testing Consortium recommended a urine CLE threshold of 140 pg/mL after careful scientific review of the results of studies describing the disposition of CLE in the horse and this threshold was adopted by the ARCI. Enzyme-linked immunosorbent assay was previously used to screen samples for CLE in Illinois, but could not detect such low concentrations in urine. Thus, a liquid-liquid extraction of CLE from urine followed by quantification by liquid chromatography-tandem mass spectrometry was developed and validated. Method validation included testing stability, ion suppression and enhancement, precision, accuracy and uncertainty. Intra-, interday and total precision and accuracy were calculated for each control and found to be within the ±15% acceptance range. The Guide to the Expression of Uncertainty in Measurement approach was used to calculate uncertainty, which was 11% at the 95% confidence level. In the past 5 years, only 15 samples were reported as positive for CLE in Illinois. This new method was used in a pilot program to screen and confirm samples received from thoroughbred and harness horses. © The Author 2014. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.
    Journal of analytical toxicology 12/2014;
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    ABSTRACT: Brain tissue may be a valuable specimen in interpretation of postmortem toxicology. The protected and isolated position of the brain eliminates or at least attenuates many of the interpretive challenges with postmortem blood specimens. This study presents data for 30 drug and drug metabolites in cases submitted to the Sedgwick County Regional Forensic Science Center for autopsy examination from 2007 to 2014. Drug concentration in heart and femoral blood is compared with the drug concentration in brain tissue. There is a positive correlation of blood to brain concentrations, thus providing another tool for the toxicologist or pathologist to utilize in case interpretation. © The Author 2014. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.
    Journal of analytical toxicology 12/2014;
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    ABSTRACT: The detection of new designer drugs is often a difficult issue in forensic urine drug testing as immunoassays are the primary screening methodology for drugs of abuse in many of these laboratories. Cross-reactivity of compounds with immunoassay kits can either aid or complicate the detection of a variety of drug and drug metabolites. For instance, emerging designer drugs that share structural similarities to amphetamines and phencyclidine (PCP) have the potential to cross-react with assays designed to detect these compounds. This study evaluates the cross-reactivity of five commercially available immunoassay reagent kits for 94 designer drugs on a Roche/Hitachi Modular P automated screening instrument. The compounds used in this study are grouped by structural class as follows: 2,5-dimethoxyamphetamines, 2C (2,5-dimethoxyphenethylamines), β-keto amphetamines, substituted amphetamines, piperazines, α-pyrrolidinopropiophenones, tryptamines and PCP analogs. A drug concentration of 100 µg/mL was used to determine cross-reactivity for each assay and resulted in the following positive rates: Microgenics DRI(®) Ecstasy enzyme assay (19%), Microgenics DRI(®) Phencyclidine enzyme assay (20%), Lin-Zhi Methamphetamine enzyme immunoassay (39%), Siemens/Syva(®) EMIT(®)II Plus Amphetamines assay (43%) and CEDIA(®) DAU Amphetamine/Ecstasy assay (57%). Of the 94 designer drugs tested, 14% produced a negative response for all five kits. No designer drug used in this study generated a positive result for all five immunoassay kits. © The Author 2014. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.
    Journal of analytical toxicology 12/2014;
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    ABSTRACT: Fentanyl is a synthetic narcotic anesthetic ∼80-100 times more potent than morphine. Owing to the potential for its abuse, the drug may be included in a forensic toxicology work-up, which requires fast, precise and accurate measurements. Here, the stability of fentanyl was assessed when stored at three different temperatures (-20, 4 and 25°C) in synthetic urine. Stability at those three temperatures was demonstrated over 12 weeks upon analysis by gas chromatography-mass spectrometry with a deuterated internal standard (fentanyl-D5) utilizing three different extraction techniques: liquid-liquid extraction (LLE), solid-phase extraction and dispersed liquid-liquid microextraction (DLLME). The DLLME method was then optimized before use in the analysis of fentanyl in urine samples obtained from autopsy cases at the El Paso County Coroner's Office. Accuracy of the DLLME method was assessed by completing spike and recovery studies at three different fortification levels (10, 100 and 250 ng/mL) with excellent recovery (89.9-102.6%). The excellent comparability between DLLME and LLE is demonstrated (Bland-Altman difference plot with a mean difference of 4.9 ng/mL) and the use of this methodology in the analysis of forensically relevant samples is discussed. © The Author 2014. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.
    Journal of analytical toxicology 12/2014;
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    ABSTRACT: The abuse of gamma-hydroxybutyric acid (GHB) and its suspicion in cases of suspected drug-facilitated sexual assault is of keen interest to forensic toxicology laboratories. This paper reports an extraction, separation and detection procedure for GHB in hair utilizing a combination of liquid-liquid extraction and solid-phase extraction using ethyl acetate and Oasis Max(®) cartridge, respectively, after the hair sample was digested. Analysis was by LC-MS-MS using a gradient separation on an Acclaim(®) Trinity(TM) P1 column performing three multiple-reaction monitoring (MRM) transitions each for GHB and its internal standard. The procedure was validated over a range from 0.4 to 50 ng/mg with estimated limit of detection (LOD) of 0.33 and an administratively set limit of quantitation (LOQ) of 1.2 ng/mg. Twenty hair specimens collected from individuals with no known exposure to GHB were analyzed for matrix interferences and to establish initial background levels of GHB. A wide range of endogenous GHB levels were observed in these samples (from less than the LOQ to 4.4 ng/mg). The results suggest the need for additional studies to better establish the full range of endogenous GHB levels in hair and that extreme caution is required in interpreting GHB findings in hair samples. Published by Oxford University Press 2014. This work is written by (a) US Government employee(s) and is in the public domain in the US.
    Journal of analytical toxicology 11/2014;
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    ABSTRACT: A 20-year-old man, a college student, became unresponsive in front of his girlfriend. He was known to consume alcohol and take an unknown drug at some point while in attendance at a local music festival earlier in the day/evening. Upon arrival of emergency personnel, he was noted to be asystolic and apneic. Despite aggressive medical intervention by emergency personnel and at a local hospital emergency room, he was pronounced deceased within 1.25 h of initial medical attention. Postmortem blood initially screened positive for methamphetamine by ELISA. An alkaline drug screen detected 5-(2-aminopropyl)benzofuran (5-APB) which was subsequently confirmed and quantified by a specific GC-MS SIM analysis following solid-phase extraction. Concentrations were determined in the peripheral blood (2.5 mg/L), central blood (2.9 mg/L), liver (16 mg/kg), vitreous (1.3 mg/L), urine (23 mg/L) and gastric contents (6 mg). No other common amphetamine-like compound was detected, although 5-(2-aminopropyl)-2,3-dihydrobenzofuran (5-APDB) was presumptively identified in both peripheral blood and urine. Alcohol, the only other drug identified, was confirmed at a concentration of 0.02% (w/v). © The Author 2014. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.
    Journal of analytical toxicology 11/2014;
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    ABSTRACT: Calculating the confidence interval is a common procedure in data analysis and is readily obtained from normally distributed populations with the familiar [Formula: see text] formula. However, when working with non-normally distributed data, determining the confidence interval is not as obvious. For this type of data, there are fewer references in the literature, and they are much less accessible. We describe, in simple language, the percentile and bias-corrected and accelerated variations of the bootstrap method to calculate confidence intervals. This method can be applied to a wide variety of parameters (mean, median, slope of a calibration curve, etc.) and is appropriate for normal and non-normal data sets. As a worked example, the confidence interval around the median concentration of cocaine in femoral blood is calculated using bootstrap techniques. The median of the non-toxic concentrations was 46.7 ng/mL with a 95% confidence interval of 23.9-85.8 ng/mL in the non-normally distributed set of 45 postmortem cases. This method should be used to lead to more statistically sound and accurate confidence intervals for non-normally distributed populations, such as reference values of therapeutic and toxic drug concentration, as well as situations of truncated concentration values near the limit of quantification or cutoff of a method. © The Author 2014. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.
    Journal of analytical toxicology 11/2014;