Toxicology findings in cases of hanging in the City and County of San Francisco over the 3-year period from 2011 to 2013.

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.

Intoxicación letal con aldicarb: análisis de sangre post mortem mediante LC-ESI-MS/MS / Fatal intoxication with aldicarb: Analysis in post mortem blood by LC-ESI-MS/MS

Antecedentes. El aldicarb es un plaguicida carbamato de alta toxicidad asociado a intoxicaciones agudas fatales en el ser humano. Su mecanismo de acción consiste en la inhibición de la enzima acetilcolinesterasa (AChE) que ocasiona la acumulación del neurotransmisor acetilcolina en la hendidura sináptica. Esta acumulación provoca síntomas colinérgicos y, dependiendo de la dosis de exposición, puede paralizar los sistemas respiratorio y nervioso hasta llegar a la muerte. Objetivo. Determinar el nivel de aldicarb en sangre post mortem en casos de intoxicación aguda. Materiales y métodos. Investigación de tipo experimental empleando un cromatógrafo líquido con espectrometría de masas, con ionización electrospray y análisis en modo tándem (LC-ESI-MS/MS). Los estándares de aldicarb y el aldicarb-d3 fueron comprados de Dr. Ehrenstorfer GmbH. El método consiste en una precipitación de proteínas de la sangre y su posterior análisis por LC-ESI-MS/MS, utilizando el aldicarb-d3 como estándar interno. El método fue aplicado a siete casos de intoxicación letal por presunta acción del aldicarb. Resultados. El aldicarb se encontró en la sangre de seis de los casos estudiados, en niveles desde 0.12 a 1.90 µg/mL. Solo en uno de los casos no se detectó aldicarb. En cuanto la presunta manera de muerte, en seis de los casos analizados fue el suicidio y en un caso se clasificó como muerte en estudio. Conclusiones. Los resultados obtenidos con la metodología analítica y la técnica LC-ESI-MS/MS son satisfactorios en términos de la determinación cuantitativa de aldicarb en sangre total post mortem. La aplicación de la metodología descrita en toxicología forense evidencia el empleo de este plaguicida en actos suicidas.

Background. Aldicarb is a high toxicity carbamate pesticide associated to human fatal acute intoxications. Its mechanism of action consists of the inhibition of the acetylcholinesterase enzyme (AChE), which induces the accumulation of the neurotransmitter acetylcholine in the synaptic cleft. This accumulation induces cholinergic symptoms and, depending on the exposition dose, it can paralyze the respiratory and nervous systems, leading to death. Objective. To determine aldicarb levels in post mortem blood in cases of acute intoxication. Materials and methods. An experimental research was conducted using liquid chromatography tandem-mass spectrometry (LC-ESI-MS/MS) with electrospray ionization. The aldicarb and aldicarb-d3 standards were purchased from Dr. Ehrenstorfer GmbH corporation. This method carries out a protein precipitation of blood and its analysis using LC-ESI-MS/MS, using aldicarb-d3 as internal standard. This method was applied to seven cases of fatal intoxication by presumable action of aldicarb. Results. Aldicarb was found in six of the studied cases on levels between 0.12 and 1.90 µg/mL. Aldicarb was not detected in blood only in one case. Six of the cases were associated to suicide as a manner of death and in one of them it remained under study. Conclusions. The results obtained with the analytical methodology and the use of the LC-ESI-MS/MS technique are satisfactory in terms of the quantitative determination of aldicarb in post mortem total blood. The application of the described methodology in forensic toxicology evidences the use of this pesticide in suicidal practices.

How reliable are parenchymal tissues for the evaluation of carbon monoxide poisoning? A pilot study.

Dealing with burnt bodies, the forensic pathologist must first of all answer the question whether the victim was alive at the moment of the fire. This study aims at clarifying whether some human solid tissues may be reliably used for the forensic diagnosis of Co poisoning on burnt bodies providing no collectable blood during the autopsy. From 34 selected cases, both cardiac blood and parenchymal samples were collected to perform CO-oxymeter, spectrophotometry, and gas chromatography tests: blood CO estimations (blood COHb% and blood[CO]) and parenchymal[CO] values have been compared with special focus on R values. The solid tissues having the best correlations with blood CO amount turned out to be the lung (R 0.84), the liver (R 0.83), the kidney (R 0.79), and the spleen (R 0.92).