This study was designed to supplement previous attempts to establish an accurate range of normal endogenous gamma-hydroxybutyrate (GHB) concentrations in random antemortem urine samples. Furthermore, its purpose was to ascertain the effect of gender, race, age, medications, and select medical conditions on endogenous concentrations of GHB in urine and the proposed endogenous urinary GHB cutoff of 10 microg/mL. Urine samples (n = 207) were provided by subjects who reported that they had never used GHB. As part of the collection process, subjects also completed a short survey to collect information about gender, race, age, orally ingested medications, and select medical conditions. All specimens were analyzed in duplicate for the presence of endogenous GHB using a previously reported headspace gas chromatography-mass spectrometry method. The data were analyzed for tendencies among different population groups. GHB concentrations ranged from 0.00 to 2.70 microg/mL in all specimens, with a median concentration of 0.24 microg/mL. Males (n = 130) had an average endogenous GHB concentration of 0.27 microg/mL (0.00-2.70 microg/mL), whereas females (n = 77) averaged 0.29 microg/mL (0.00-0.98 microg/mL). Select medical conditions and participants' race, age ranges, and medications that were used within 48 h prior to collection were also evaluated. We believe this to be the most comprehensive study on endogenous GHB concentrations in urine to date. The results of this study will aid the interpretation of low GHB concentrations measured in urine samples, particularly in investigations of drug-facilitated crimes.

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Samples from a self-proclaimed cocaine (COC) user, from 19 drug users (postmortem) and from 27 drug chemists were extensively washed and analyzed for COC, benzoylecgonine, norcocaine (NC), cocaethylene (CE) and aryl hydroxycocaines by liquid chromatography-tandem mass spectrometry. Published wash criteria and cutoffs were applied to the results. Additionally, the data were used to formulate new reporting criteria and interpretation guidelines for forensic casework. Applying the wash and reporting criteria, hair that was externally contaminated with COC was distinguished from hair collected from individuals known to have consumed COC. In addition, CE, NC and hydroxycocaine metabolites were only present in COC users' hair and not in drug chemists' hair. When properly applied, the use of an extended wash, along with the reporting criteria defined here, will exclude false-positive results from environmental contact with COC.

The use of fast gas chromatography-mass spectrometry (FGC-MS) was investigated to improve the efficiency of analysis of urine specimens that previously screened presumptively positive for amphetamine (AMP), methamphetamine (MAMP), 3,4-methylenedioxyamphetamine (MDA), 3,4-methylenedioxymethamphetamine (MDMA), and/or 3,4 methylenedioxyethylamphetamine (MDEA) by immunoassay testing. Specimens were pretreated with basic sodium periodate, extracted using a positive-pressure manifold/cation-exchange solid-phase cartridge methodology, and derivatized using 4-carbethoxyhexafluorobutyryl chloride (4-CB). The analytical method was compared to traditional GC-MS analysis and evaluated with respect to assay chromatography, linearity, sensitivity, precision, accuracy, and reproducibility. The limits of detection were 62.5 ng/mL for MDA and 31.25 ng/mL for AMP, MAMP, MDMA, and MDEA. All of the target analytes were linear to 12,000 ng/mL with the exception of MAMP which was linear to 10,000 ng/mL. The intra-assay precision of a 500 ng/mL multiconstituent control (n=15) ranged from 522.6 to 575.9 ng/mL with a coefficient of variation of less than 3.8%. Authentic human urine specimens (n=187) previously determined to contain the target analytes were re-extracted and analyzed by both FGC-MS and the currently utilized GC-MS method. No significant differences in specimen concentration were observed between these analytical methods. No interferences were seen when the performance of the FGC-MS method was challenged with ephedrine, pseudoephedrine, phenylpropanolamine, and phentermine. When compared to traditional GC-MS analysis, FGC-MS analysis provided a dramatic reduction in retention time for amphetamine (1.8 min vs. 4.12 min). For example, the FGC-MS method reduced overall run time for a batch of 56 specimens from 12.0 h to 7.25 h. This reduction in analysis time makes FGC-MS an attractive alternative to traditional GC-MS by allowing a laboratory greater flexibility in the purchase and use of capital equipment and in the assignment of laboratory personnel, all resulting in greater overall efficiency by decreasing reporting times for AMP, MAMP, and designer amphetamine positive specimens.

We present a case that underscores the potential cardiotoxicities of these medications. Ziprasidone and bupropion ingestion can be associated with cardiotoxicities that may require several days of aggressive cardiac monitoring and treatment.