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Lung D.D.,University of California at San Francisco | Lemos N.P.,University of California at San Francisco | Lemos N.P.,Forensic Laboratory Division
Forensic Toxicology | Year: 2014

We reviewed postmortem fentanyl cases to compare peripheral blood (PB) concentrations between deaths caused by fentanyl and deaths in which fentanyl was incidental. Furthermore, we describe PB concentrations in fentanyl-caused deaths with and without transdermal (TD) fentanyl use. Our review produced 20 cases with PB fentanyl. Of these, 13 were determined to be fentanyl-caused deaths. Eight of the 13 involved TD fentanyl. The remaining 7 cases were decedents undergoing therapy with fentanyl (TD, n = 3; intravenous, n = 4). In the 13 fentanyl-caused deaths, the mean PB fentanyl level was 30.1 ng/ml. In the deaths involving TD fentanyl use, the mean fentanyl level was 41.7 ng/ml. Deaths without TD fentanyl use had a mean fentanyl level of 21.3 ng/ml. There were 7 other cases with incidental fentanyl. In 3 of these, therapeutic TD fentanyl was used and the mean PB concentration was 16.6 ng/ml. In the remaining 4 deaths in which therapeutic intravenous fentanyl was employed, the mean PB fentanyl level was 8.1 ng/ml. Our review suggests that a PB fentanyl concentration equal to or greater than 25 ng/ml indicates that fentanyl should be considered as being contributory to or the cause of death. However, ranges of measured PB concentrations are once again shown to overlap between subjects who overdose and those who use fentanyl as prescribed. In addition, fentanyl-caused deaths involving TD fentanyl exposure have higher PB fentanyl concentrations than those who did not use transdermal patches. Although enlightening, our study suggests that further evaluation of fentanyl concentration variability among different postmortem blood specimens is needed. © 2013 Japanese Association of Forensic Toxicology and Springer Japan.

Lemos N.P.,Forensic Laboratory Division | Lemos N.P.,University of California at San Francisco
Journal of Forensic Sciences | Year: 2014

The case of a 22-year-old male Caucasian driver is presented. He was involved in a traffic collision. At the roadside, he displayed blank stare and mellow speech with a barely audible voice. A DRE found low body temperature, rigid muscle tone, normal pulse, lack of horizontal and vertical gaze nystagmus, nonconvergence of the eyes, dilated pupil size, and normal Pupillary reaction to light. A standard toxicology DUID protocol was performed on the driver's whole blood including ELISA and GC-MS drug screens with negative results. Additional drug screening was undertaken for bath salts and synthetic cannabinoid receptor agonists by LC-MS/MS by a commercial laboratory and identified the synthetic cannabinoid receptor agonist XLR-11 in the driver's blood. XLR-11 was subsequently quantified at 1.34 ng/mL. This is the first documented case involving a driver operating a motor vehicle under the influence of the synthetic cannabinoid receptor agonist XLR-11. © 2014 American Academy of Forensic Sciences.

Oostdik K.,Promega Corporation | Lenz K.,Promega Corporation | Nye J.,Michigan State Police | Schelling K.,Michigan State Police | And 26 more authors.
Forensic Science International: Genetics | Year: 2014

The original CODIS database based on 13 core STR loci has been overwhelmingly successful for matching suspects with evidence. Yet there remain situations that argue for inclusion of more loci and increased discrimination. The PowerPlex® Fusion System allows simultaneous amplification of the following loci: Amelogenin, D3S1358, D1S1656, D2S441, D10S1248, D13S317, Penta E, D16S539, D18S51, D2S1338, CSF1PO, Penta D, TH01, vWA, D21S11, D7S820, D5S818, TPOX, DYS391, D8S1179, D12S391, D19S433, FGA, and D22S1045. The comprehensive list of loci amplified by the system generates a profile compatible with databases based on either the expanded CODIS or European Standard Set (ESS) requirements. Developmental validation testing followed SWGDAM guidelines and demonstrated the quality and robustness of the PowerPlex® Fusion System across a number of variables. Consistent and high-quality results were compiled using data from 12 separate forensic and research laboratories. The results verify that the PowerPlex® Fusion System is a robust and reliable STR-typing multiplex suitable for human identification. © 2014 The Authors.

Lemos N.P.,Forensic Laboratory Division | Lemos N.P.,University of California at San Francisco | Ingle E.A.,Forensic Laboratory Division
Journal of Analytical Toxicology | Year: 2011

Cannabinoids are often excluded from postmortem toxicology screens due to their ubiquitous nature, interpretative difficulties and unanswered questions regarding their postmortem redistribution. In this study, we review 30 postmortem cases where a drug screen gave a positive cannabinoids result and a confirmation identified Δ 9-tetrahydrocannabinol (THC), 11-hydroxy-Δ 9-tetrahydrocannabinol (11-OH-THC), and/or 11-nor-9-carboxy-Δ 9-tetrahydrocannabinol (THC-COOH) in peripheral (BL-P) or cardiac/central blood (BL-C) and/or urine (UR). Had cannabinoids not been included in these toxicologic evaluations, incomplete or erroneous inferences would have been drawn in a substantial number of cases regarding cause/manner of death. THC was detected in 28 BL-C and in all 30 BL-P. THC and THC-COOH were confirmed present in 2 and 23 UR, respectively. 11-OH-THC was detected in 4 BL-C, 6 BL-P, and 0 UR. The mean THC concentrations in BL-C and BL-P were 8.0 and 15.8 ng/mL, respectively. The mean THC-COOH concentrations in BL-C and BL-P were 55.2 and 60.6 ng/mL, respectively. The mean 11-OHTHC concentrations in BL-C and BL-P were 17.0 and 12.5 ng/mL, respectively. Postmortem interval (PMI) for each case was determined and evaluated in relation to BL-C/BL-P concentration ratios with THC-COOH exhibiting a possible trend. This study is the first of its kind and demonstrates the usefulness of cannabinoid analyses as part of death investigations. Furthermore, it provides distribution data that will improve the ability of toxicologists and pathologists to evaluate cannabinoid concentrations in human postmortem specimens.

San Nicolas A.C.,Forensic Laboratory Division | Lemos N.P.,Forensic Laboratory Division
Forensic Science International | Year: 2015

In postmortem cases where the cause of death is hanging, toxicological analyses may be considered unnecessary by some medical examiners, toxicologists, and other persons involved in medico-legal investigations because the cause of death seems "obvious." To ascertain if toxicological analyses are necessary when the cause of death is hanging, all 102 hanging cases (25 females; 77 males) from 2011 to 2013 that came under the jurisdiction of the San Francisco Office of the Chief Medical Examiner were examined from a total of 3912 sudden, unexpected, or violent death cases in the same period. Suicide was the manner of death in 99 of these cases, with two accidental and one undetermined death. The average age of decedents was 43.9 years (median 41), the youngest was an 11-year old male and the oldest was an 86-year old female. Of the 102 cases, 33 had negative toxicology while 69 cases had at least one positive toxicology result. Females were equally likely to have negative or positive results (12 and 13 cases respectively), but males were 37.5% more likely to have positive toxicology (n= 56) rather than negative toxicology (n= 21). For females, alcohol, mirtazapine, venlafaxine, and trazodone were the top psychoactive substances in peripheral blood while THC, cocaine, hydrocodone, bupropion, olanzapine, doxylamine, quetiapine and dextromethorphan were also reported. For males, alcohol, THC, cocaine, amphetamine, methamphetamine, bupropion, and diphenhydramine were the top psychoactive substances in blood, but several other drugs were also found in individual cases. Our study of hanging cases over a 3-year period support the idea that complete postmortem toxicology investigation of hangings should be performed, even when the "obvious" cause of death is asphyxia due to hanging. Many of these cases involved psychoactive substances (most often alcohol and cannabis), and having such knowledge provides a better understanding of the circumstances surrounding the decedent's death, their possible state of impairment, including the possibility of a staged suicide if the decedent was too impaired to perform a self-hanging. © 2015 Elsevier Ireland Ltd.

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