Poison hemlock determination in postmortem samples.

Poison hemlock (Conium maculatum L.) is a weed that grows rampant in many areas of North America. Forensic toxicology laboratories rarely receive requests to analyze biological specimens for the presence of poison hemlock. This report discusses two postmortem cases that were encountered over a decade apart and describes different analytical approaches that may be used to quantify coniine, a primary poison hemlock alkaloid, in biological specimens. The first case is from 2004 and involves a 27-year-old female that was found deceased in a relatively isolated area of California. Based on the presence of plant material at the scene and signs of its ingestion at autopsy, the possibility of hemlock poisoning was considered. Toxicological testing of the blood and gastric content by quantitative selected-ion monitoring Gas Chromatography/Mass Spectrometry (SIM-GC/MS) revealed the presence of coniine at concentrations of 410 ng/mL and 9300 ng/mL, respectively. The second case is from Pennsylvania and was sent for analysis in the spring of 2019. In this case, a male in his forties was found deceased in the kitchen area of a camper. Green substances, in liquid and residue forms, were observed in the sink. Mixtures of leaf-like material were also found in several bowls and pans. Subclavian blood screened positive for coniine by full-scan Gas Chromatography/Mass Spectrometry (GC/MS). Semi-quantitative confirmation testing was performed by Liquid Chromatography Tandem Mass Spectrometry (LC-MS/MS) and showed the presence of coniine at a concentration of 35 ng/mL. These analytical approaches can be used to substantiate or exclude poison hemlock exposure as a cause of death.

Melatonin Supplementation in Undetermined Pediatric Deaths.

Since 2015, the North Carolina Office of the Chief Medical Examiner has investigated seven deaths of infants and toddlers, aged 2 months to 3 years, with exogenous melatonin detected upon toxicological analysis. Melatonin concentrations ranged from 3 to 1,400 ng/mL in postmortem whole blood. While the cause and the manner of all seven deaths were classified as undetermined, the analytical findings are noteworthy. Melatonin is generally considered a safe, natural product appearing in many over-the-counter supplements geared toward young children to facilitate calmness and improve sleep. Melatonin is a neurohormone, which regulates not only circadian rhythms and natural sleep but also other physiological functions. Endogenous melatonin production, derived from essential amino acid metabolism, does not begin until pineal gland maturation at ∼3 months of age with concentrations in plasma peaking during periods of darkness at ∼0.2 ng/mL. Administering commercially available melatonin supplements to infants results in levels substantially greater than endogenous sources, which should not be assumed to be safe just because of their endogenous nature. The finding of exogenous concentrations in some postmortem pediatric cases warrants attention. Several topics of interest surrounding these postmortem melatonin findings will be considered, such as minimal regulatory control over commercial products as well as the potential impact on hazardous sleeping conditions. This manuscript will outline the physiological effects of melatonin and detail the case studies from the North Carolina medical examiner system. Forensic toxicology laboratories should consider including melatonin at exogenous concentrations in their testing schemes for appropriate postmortem infant and toddler cases.

Validation of a Fully Automated Immunoaffinity Workflow for the Detection and Quantification of Insulin Analogs by LC-MS-MS in Postmortem Vitreous Humor.

The analysis of biological specimens collected at autopsy for the presence of exogenous insulin(s) is of special interest in select death investigations as they may be suspected in the cause of a death. Technical challenges include the limited stability of insulin, and the forensic requirement of differentiating endogenous insulin from pharmaceutical analogs. A novel method was developed for the detection and quantification of human insulin, Glulisine, Lispro, Aspart, Glargine and Detemir in vitreous fluid. An immunoaffinity extraction procedure is performed followed by separation of the insulin α- and ß-chains. Liquid chromatography tandem mass spectrometry analysis of the ß-chain allows for the unequivocal identification of each insulin analog. The analytical measurement range for each insulin was 0.5-25 ng/mL. The method was evaluated for accuracy, precision, carryover, interferences and stability. Eight vitreous fluid samples collected from cases where untoward insulin use was suspected were subjected to analysis. Positive results were obtained from three samples, and a detailed case history is provided for one of these cases. Even though insulin instability in postmortem biological fluid remains a challenge, this method allows for a reliable forensic-level analysis in vitreous fluid.

The Importance of Melatonin Detection in Pediatric Deaths.

Melatonin is an endogenous hormone that regulates sleep patterns. It is available in varying formulations and dosages and is marketed as a natural substance that can alleviate insomnia. Recent news reports indicate that melatonin has been administered without appropriate authorization in daycare settings. Even though lethal outcomes have not been solely attributed to exogenous melatonin overdose, it has been relevant to select police and postmortem investigations. A quantitative liquid chromatography-tandem mass spectrometry (LC-MS/MS) assay was developed for the analysis of biological specimens. Results of 22 positive blood samples were evaluated based upon gender, age, and melatonin concentration from cases submitted by clinical, police, and death investigation agencies. Two cases are described. In Case 1, a 9-month-old was found unresponsive after cosleeping with a sibling. Allegations included exposure to an unspecified pesticide and dextromethorphan, and consumption of half a cigarette. There was admitted use of melatonin. Melatonin was quantified in blood and gastric fluid at concentrations of 13 ng/mL and 1200 ng/mL, respectively. In Case 2, a 13-month-old was found nonresponsive in a shared room. Melatonin was found within some of the sippy cups. The infant was extremely warm to the touch. Resuscitative efforts were unsuccessful and death was pronounce3d. Analysis showed a result of 210 ng/mL in blood. The presented quantitative LC-MS/MS method can successfully be applied to evaluate exposure to exogenous melatonin. Toxicology testing can assist in the investigation of these case types by substantiating the purposeful administration of melatonin.

Illicit Drug Delivery Via Administration of Human Blood.

The physiological, psychological, and social consequences associated with illicit drug use are well documented. In addition to the effects directly related to the drug(s), the delivery mechanism can precipitate other serious health conditions. A case is reported where an individual stopped by law enforcement was discovered to be in possession of a vial containing a red-colored fluid, which the person stated was blood and contained fentanyl. Analysis by headspace GC, ELISA, and LC-TOF/MS screening in with mass spectral confirmation revealed the presence of several substances, including ethanol, methamphetamine, amphetamine, MDA, 6-monoacetylmorphine, codeine, morphine, alprazolam, delta-9 THC, ephedrine, pseudoephedrine, and norpseudoephedrine; serology testing verified the fluid was consistent with human blood. Methamphetamine was present at a dosage form amount (11 mg). The purpose of this study was to detail the analytical findings, interpret their meaning, and discuss the public health concerns associated with the drug delivery by the administration of human blood.

The Utility of Bile in Postmortem Forensic Toxicology.

Bile is one matrix type that may be collected at autopsy and submitted to the toxicology laboratory for analysis. Because it is an excretion product of the liver, it can be used for screening purposes and to determine what drugs an individual used or was exposed to prior to death. This paper presents collection and analytical considerations of bile, and provides an overview of its utility from a testing and interpretation perspective. Acad Forensic Pathol. 2018 8(2): 324-327.

Synthetic cannabinoid drug use as a cause or contributory cause of death.

Adverse effects associated with synthetic cannabinoid use include agitation, psychosis, seizures and cardiovascular effects, all which may result in a lethal outcome. We report the collection of data from 25 medical examiner and coroner cases where the presence of synthetic cannabinoids was analytically determined. Participating offices provided case history, investigative and relevant autopsy findings and toxicology results along with the cause and manner of death determination. This information, with the agency and cause and manner of death determinations blinded, was sent to participants. Participants offered their opinions regarding the likely contribution of the toxicology findings to cause and manner of death. The results show that some deaths are being attributed to synthetic cannabinoids, with the highest risk areas being behavioral toxicity resulting in excited delirium, trauma or accidents and as contributing factors in subjects with pre-existing cardiopulmonary disease. While insufficient information exists to correlate blood synthetic cannabinoid concentrations to effect, in the absence of other reasonable causes, the drugs should be considered as a cause or contributory cause of death based on history and circumstances with supporting toxicological data.

The Determination of Insulin Overdose in Postmortem Investigations.

The analysis of biological specimens for the presence of exogenous insulin is of special interest in select postmortem investigations. Insulin analogues are primarily used to mediate the regulation of blood glucose concentrations; however, their use has also been implicated or suspected as a cause of death in suicides, accidents, and homicides. Toxicological analysis for these compounds is challenging due to the large molecular weight, the limited stability of insulin in whole blood, and complexities associated with sample preparation and instrumental testing. As a consequence, determination of insulin in postmortem specimens is not routinely offered by most forensic toxicology laboratories. Forensic death investigation is further complicated by interpretative difficulties such as the frequent absence of anatomical findings, concentration interpretation in known insulin users, and addressing the impact of chemical instability and postmortem redistribution. There are ongoing efforts, however, to develop and validate robust methods that may be used for this analysis on these challenging samples and that are capable of withstanding scientific and legal scrutiny for forensic use. In this regard, in recent years, methods for the detection of exogenous insulin in postmortem samples have been reported and results of this testing has been published in a handful of cases. The purpose of this article is to review the primary functions of insulin, the disease states associated with the therapeutic use of exogenous insulin, the current state of laboratory testing, and to provide case summaries that summarize the timeline of advancements and underscore the importance of this work.