Forensic Chemistry Research Articles

Untargeted toxicology in sudden cardiac arrest victims

Abstract Funding Acknowledgements Type of funding sources: Public grant(s) – EU funding. Main funding source(s): European Union’s Horizon 2020 research and innovation programme to J.T.-H under acronym ESCAPE-NET Background Sudden cardiac arrest (SCA) is a major public health challenge and is associated with poor outcomes. Many drugs are known to increase risk of arrythmias and ultimately sudden cardiac death. To our knowledge an untargeted toxicological analysis has not previously been performed in an initially resuscitated SCA cohort. Purpose We aimed to determine the qualitative and quantitative drug composition present in SCA patients by using forensic toxicological analytical chemistry of all illicit, non-prescription and prescribed drugs, and further investigate whether these drugs are in therapeutic levels or overdosed and to correlate the clinical findings with the toxicology results. Methods We performed a prospective single-tertiary-center study and included all SCA victims (aged 18-90 years) admitted to our cardiac intensive care unit, between February 2019 to November 2019 (Figure 1). Traumatic and overt overdose related SCA were not included in the study. Drugs used during resuscitation and administered prior to sample collection were identified in each patient and excluded. Results We prospectively identified 85 all-cause SCA patients with a median age of 60 years (IQR: 53-71) and male predominance (80%). The majority had a shockable rhythm as first rhythm (95%). The major cause of cardiac arrest was acute and chronic ischemia (56/77, 66%), followed by cardiomyopathy (9/77, 12%), idiopathic ventricular fibrillation (8/77, 10%), bradycardia (2/77, 2.6%), primary arrhythmia (1/77, 1.3%), other (1/77, 1.3%). The remaining 8 patients (9.4%) died prior to diagnosis. A positive toxicology was identified in 67 patients (79%) with a total of 218 detected drugs. The most frequent drugs were mild analgesics (32/85, 38%), beta-blockers (21/85, 25%) and ACE-inhibitors/ARB (20/85, 24%). A total of 9 (11%) patients had one or more potentially abusable drugs detected, with the most common being opioid agonists in 5 patients (Figure 2). Importantly, all drugs were found at sub-therapeutic or therapeutic concentrations. None had overdose concentrations. Moreover, polypharmacy was common and a median of 2 drugs (IQR: 1-4) were detected (excluding caffeine that was detected in 83 patients). Conclusion We found that the majority had drugs detected, and polypharmacy is displayed in a considerable proportion. Potentially abusive drugs were encountered in 11%. However, we did not identify any occult overdose related cardiac arrests among all resuscitated SCA patients. In our setting, toxicological screening in cardiac arrest patients who is not obviously overdosed is excessive.

Profile of explosives's use in ATMs/cash safes robberies in Brazil.

This retrospective study reports data obtained by the Federal Police's National Institute of Criminalistics (INC-PF) relating to chemical analysis aimed at identifying explosives used in Automated teller machines (ATMs)/cash safes robberies between 2014 and 2020 in Brazil. 93 Real cases were studied and, based on the analysis carried out on the materials related to these cases, focusing on the type of explosive used, the following distribution profile was obtained: I) explosive mixtures based on chlorates and/or perchlorates (53%); explosive emulsion (22%); black gunpowder (13%); negative/inconclusive (11%) and organic - pentaerythritol tetranitrate (PETN) (1%). These results can contribute to investigations related to diversion/loss of explosives for criminal purposes, indicating, for example, through relationships between prevalence in the use of a certain type of explosive with a certain location, its possible origin (mining industry, explosive industries, fireworks factories, among others). The profile observed in the results can guide the selection of explosives to be studied in future research, as the possibilities are vast. Furthermore, despite the expressive number of occurrences in Brazil in the period of interest of this study, only a small fraction of samples was sent to the forensic chemistry laboratory to identify the explosive involved, which suggests that expanding chemical analysis should be encouraged in this field. In combination with an increase in professional training and collaboration trials between the laboratories, these activities can improve the chemical explosive's profile in Brazil, enabling the search for correlations between occurrences and contributing to the growth and development of this area.

A sustainable approach for the stability study of psychotropic substances using vitreous humor and liver as alternative matrices

The stability of psychotropic substances representing various drug groups important from the perspective of forensic chemistry, including benzodiazepines, antidepressants, carbamazepine, cocaine, and their selected metabolites, was investigated for 1 month in two alternative biological matrices, vitreous humor and liver homogenate. Three different thermal storage conditions (−20, 4, and 20 °C) were tested. Liquid chromatography-mass spectrometry (LC-MS) analysis was preceded by an effective solid-phase microextraction (SPME) procedure. The results were statistically analyzed using one-way ANOVA to find significant concentration variations over time. The results obtained allowed for dividing the analytes into four groups: stable under all tested conditions, only at −20 and 4 °C, only at 20 °C, and overall unstable. Nordiazepam, venlafaxine, and cocaine and its metabolites turned out to be the most unstable substances, while fluoxetine showed the highest storage stability in both matrices. The SPME/LC-MS method was comprehensively evaluated according to the principles of white analytical chemistry (WAC), which reconcile the greenness and functionality of the method. A close to 100% whiteness score proves its sustainability and suitability for the intended application.Graphical abstract

Portable testing techniques for the analysis of drug materials

AbstractThe analysis of drug material in the field is an important function of law enforcement agencies, forensic drug laboratories, and drug checking services. Portable testing techniques employed by these different groups range from inexpensive screening tools with low discriminating power, such as presumptive chemical color tests, to more sophisticated portable analytical techniques that behave as miniaturized versions of their laboratory counterparts, such as gas chromatography–mass spectrometry (GC–MS). Rapid non‐destructive analysis in the field and non‐laboratory environments is afforded by portable and handheld Fourier transform infrared (FTIR) spectrometers with little to no sample preparation, while handheld Raman analyzers have the added potential for drug material identification through sealed packaging using spatially offset Raman spectroscopy (SORS). Utilization of the most suitable testing technique for the given environment is demonstrated at international borders and airports wherein ion mobility spectroscopy (IMS) is frequently employed for the detection of drug (and explosive) residues owing to its ease of operation and rapid analysis. Advances in technology and materials have provided analysts with new portable testing techniques, including paper spray ionization–MS (PSI‐MS), an ambient MS technique that provides sensitive, rapid, and reliable analysis without the need for sample preparation steps. A growing area of research and interest in the development of sensitive and selective optical and electrochemical portable (bio)sensors for in‐field analysis of drug material indicates that new commercial sensors for drug detection will be available in the foreseeable future.This article is categorized under: Forensic Chemistry and Trace Evidence > Controlled and Emerging Drug Compounds Forensic Chemistry and Trace Evidence > Emerging Technologies and Methods Toxicology > Drug Analysis

Portable Raman spectroscopy applied to the study of drugs of abuse.

The use of drugs of abuse has grown significantly in recent decades. In forensic chemistry, methods of identifying and characterizing illicit drugs contribute to the interests of researchers, experts, and public security authorities. Among existing methods, portable Raman spectroscopy is notable for performing rapid, non-destructive, and highly selective analysis in the laboratory or on-site. When the resulting spectral data are paired with chemometric tools, methods of exploratory analysis and multivariate calibration can be developed. Thus, this work describes the application of Raman spectroscopy associated with principal component analysis (PCA) and interval principal component analysis (iPCA) to assessing trends in samples of cocaine (n= 40), crack (n= 33), and their main adulterants (n= 5) and diluents (n= 5), tablets of ecstasy (n= 14), designer drugs papers (n= 27), and alcoholic solutions adulterated with benzodiazepines (alprazolam and diazepam). In addition, competitive adaptive reweighted sampling (CARS) combined with partial least squares (PLS) regression (CARSPLS) was used to quantify adulterants (benzocaine, lidocaine, and procaine) in binary mixtures with crack (n= 21) and solutions of cachaça adulterated with bromazepam (n= 11).

Case-Based Instruction in the Forensic Chemistry Classroom: Effects on Students' Motivation and Achievement

Forensic chemistry students need to be motivated and develop critical thinking, problem-solving, and higher-order thinking skills and not just accumulate many facts to be good evidence collectors and investigators in the future. As case-based instruction has been utilized in various fields to this effect, this study aimed to determine the effects of such a method on students' motivation towards forensic chemistry learning and their success in understanding the taught concepts through their achievement scores. A pre-test post-test control group design was employed to involve two forensic chemistry classes with 42 students each, identified through the purposive sampling technique. One class was taught through case-based instruction, while the other through the lecture method. The classes were assigned to experimental and control groups to examine the study's treatment process effects through a coin toss. The t-test for independent samples was used to determine significant differences in students' pre/post-test scores in the treatment and the control group for the motivation and achievement tests. The two groups of respondents exhibited increased motivation and achievement mean scores with significant differences. However, those exposed to case-based instruction had higher mean scores than those taught with the lecture method. Thus, the use of case-based instruction in the forensic chemistry classroom promotes critical thinking, problem-solving, and higher-order thinking skills leading to significant positive changes in the motivation and achievement of students in the course. Therefore, case-based education is recommended as it is expected to make positive contributions to the forensic chemistry teaching process and science education.

Electrochemical Detection of Dinitrobenzene on Silicon Electrodes: Toward Explosives Sensors

Detection of explosives is vital for protection and criminal investigations, and developing novel explosives’ sensors stands at the forefront of the analytical and forensic chemistry endeavors. Due to the presence of terminal nitro groups that can be electrochemically reduced, nitroaromatic compounds (NACs) have been an analytical target for explosives’ electrochemical sensors. Various electrode materials have been used to detect NACs in solution, including glassy carbon electrodes (GCE), platinum (Pt), and gold (Au) electrodes, by tracking the reversible oxidation/reduction properties of the NACs on these electrodes. Here, we show that the reduction of dinitrobenzene (DNB) on oxide-free silicon (Si–H) electrodes is irreversible with two reduction peaks that disappear within the successive voltammetric scanning. AFM imaging showed the formation of a polymeric film whose thickness scales up with the DNB concentration. This suggest that Si–H surfaces can serve as DNB sensors and possibly other explosive substances. Cyclic voltammetry (CV) measurements showed that the limit of detection (LoD) on Si–H is one order of magnitude lower than that obtained on GCE. In addition, EIS measurements showed that the LoD of DNB on Si–H is two orders of magnitude lower than the CV method. The fact that a Si–H surface can be used to track the presence of DNB makes it a suitable surface to be implemented as a sensing platform. To translate this concept into a sensor, however, it would require engineering and fabrication prospect to be compatible with the current semiconductor technologies.

Quantitative determination of five cannabinoids in blood and urine by gas chromatography tandem mass spectrometry applying automated on-line solid phase extraction.

Cannabis is the most frequently consumed illegal substance worldwide. More recently, an increasing number of legal cannabis products low in psychoactive Δ9‐tetrahydrocannabinol (THC) but high in non‐intoxicating cannabidiol (CBD) are being more widely consumed. While the detection and quantification of THC and its metabolites in biological matrices is an important forensic‐toxicological task, additional detection of CBD is also important, for example, when examining the plausibility of consumer's statements. This report describes the method validation for the quantitative determination of THC and its two major metabolites, 11‐hydroxy‐THC (OH‐THC) and 11‐nor‐9‐carboxy‐THC (THC‐COOH), as well as CBD and cannabinol (CBN) in whole blood and urine. The method employs automated on‐line solid phase extraction coupled to gas chromatography tandem mass spectrometry (GC–MS/MS). The method was fully validated according to guidelines of the Swiss Society of Legal Medicine (SGRM) and the Society of Toxicological and Forensic Chemistry (GTFCh). The method fulfilled the validation criteria regarding analytical limits, accuracy and precision, extraction efficacy, and sample stability. The limits of detection (LODs) in whole blood and urine were 0.15 ng/mL for THC, OH‐THC and CBD, 0.1 ng/mL for CBN, and 1.0 ng/mL for THC‐COOH. The limits of quantification (LOQ) in whole blood and urine were 0.3 ng/mL for THC, OH‐THC and CBD, 0.2 ng/mL for CBN, and 3.0 ng/mL for THC‐COOH. The fully validated and automated method allows sensitive and robust measurement of cannabinoids in whole blood and urine. Detection of CBD provides additional information regarding consumed products.

Identification of synthetic cathinones in seized materials: A review of analytical strategies applied in forensic chemistry

AbstractSynthetic cathinones are a class of novel psychoactive substances, commonly tested in seized materials by forensic chemistry laboratories. These drugs have been found in different types of seized materials including powders, tablets, liquids, herbs, and blotters. A comprehensive review of the literature shows that the analyses of synthetic cathinones have been performed by a diverse repertoire of techniques, from more traditional to emerging methods. Techniques commonly used in the analysis of “traditional” illicit drugs, such as color and microcrystalline tests, chromatography, capillary electrophoresis, mass spectrometry (MS), and infrared (IR), and Raman spectroscopies, have been used for screening and/or confirmatory purposes, depending on the technique and laboratories preference. However, other emerging techniques, such as nuclear magnetic resonance, high‐resolution MS, direct analysis in real‐time MS, gas chromatography with IR detection, and so on, have been drawing the attention of forensic scientists due to the advantages of these techniques in providing important structural data. It is important to consider that each technique presents analytical benefits and limitations, which should be considered when analyzing synthetic cathinones in seized materials. Furthermore, the combination of more than one analytical technique is always recommended, especially when an unknown synthetic cathinone is suspected and/or encountered in the sample.This article is categorized under: Forensic Chemistry and Trace Evidence > Controlled and Emerging Drug Compounds Toxicology > New Psychoactive Substances Forensic Chemistry and Trace Evidence > Emerging Technologies and Methods

New Trends in Analytical Chemistry for the Examination and Interpretation of Traces of Crimes

Forensic sciences are generally described as the application of the scientific method to the analysis of traces in order to identify the authorship and materiality of a crime . Forensic scientists evaluate different types of materials, and the type of scientific method and techniques employed depend on the questions to be answered within a given context . Forensic chemistry is one of the most far-reaching areas within the forensic science field. With the increase in technology and the development of analytical techniques, chemistry has been used more and more to elucidate legal controversies. Therefore, knowledge in chemistry is indispensable to solve crimes. In this letter, the applications of analytical chemistry will be discussed within emerging forensic themes: the determination of the origin of seized drugs (chemical profiling), the investigation of document fraud, and the valuation analysis of pieces of art. Chemical profiling consists of a series of chemical analyses that provide the concentration of the components present in the seized drugs, present as major or minor components, or event those present only in trace levels. Using different analytical methods, complex chemical profiles are obtained for each drug sample analyzed, giving these samples a chemical “signature” based on the presence of impurities of natural origin. and added diluents/adulterants. Therefore, such studies generate relevant data that make it possible to establish connections between samples and materials of different seizures, classifying them into chemically correlated groups. Through these connections, it is possible to establish specific links among suppliers, drug dealers, and users, designing distribution network patterns and providing subsidies for the identification of the origin of the drug, including its geographical origin. Another striking forensic application of analytical chemistry is age determination and the authenticity of papers and inks. Once an ink is deposited on a support (paper), it is exposed to air, light, and moisture, and the following physical–chemical processes occur: coloration degradation, solvent evaporation, and hardening (polymerization) of the resins. These processes have been used in the complex task of determining the absolute or relative (comparative) age of manuscripts on paper. The largest number of publications refer to ballpoint pen inks. Ezcurra and collaborators published a comprehensive review on the dating of paints by modern instrument writers. Analytical paint dating exams essentially consist of quantifying how paint components vary over time. Last but not least, the authentication of pieces of art used as a tool to fight crime is a recent area of activity of analytical chemistry in Brazil. Operation Lava Jato shed light on the possibility that criminal use of the art market is a widespread method among agents of corruption and that it is much more complex and structured than previously thought. It is up to criminal experts to determine the authenticity of a piece of art. In general, the analytical investigations are guided by the identification and quantification of substances used in the production of the art piece, using non-destructive methodologies, such as Raman spectroscopy.

Forensic Analytical Chemistry: Connecting Science and Justice

Currently, analytical chemistry is more than simply its division into classical and instrumental. It is an interdisciplinary area that involves notions of biology, toxicology, statistics, computer science, and physics, among others. There are several areas of knowledge applied in the development of a chemical analysis, which is configured as all the processes necessary for the identification and quantification of the different components of a sample. When this sample is a trace material from a crime scene, analytical chemistry assumes a central role in the conversion of this sample into material evidence with legal value through consolidated and validated procedures, obtained by exhaustive investigative and methodological studies. The responsibility assumed is in the confidence of the result obtained, which will only be possible with the validation of the method. Although not all methods are perfect, a quantitative determination requires a precise and accurate methodology. Therefore, analytical chemistry is very important to forensic chemistry. Material evidence has a great influence on a trial because it is clothed in technical characteristics, and the expectation is that it will help to unequivocally clarify the truth of the facts. It is this expectation that makes the work of the analytical chemist so important in conducting an analytical procedure for forensic purposes. The result obtained may or may not incriminate someone. Another analytical challenge in forensic analysis is the collection and preparation of a sample that has a criminal trace profile. Such procedures should preserve as much of the criminal evidence as possible. At a crime scene, several samples can be considered evidence: soils, fibers, glass, gunshot residues, explosives, among others. Locard's principle of exchange states that whenever two objects come into contact, an exchange of materials occurs between them and, thus, a connection is established between the suspect and the crime scene or between the suspect and the victim based on the transfer of fragments of the materials. Once again, analytical rigor will play a relevant role in the preservation and experimental conduct of the traces. A failure in the analytical procedure may make it impossible to use a trace as material evidence in a court of law, jeopardizing its use in the conviction of the judge or jury. It is up to the forensic analysts to provide a result with credibility and legal security, i.e., to rigorously follow the analytical protocols. Forensic research is dynamic. One example is the demand for analytical methods that encompass the wide variety of newly emerging psychoactive substances (NPS), formerly known as "designer drugs", which must continually be detected and catalogued. In the Interview in this volume, Dr. Barry Logan tells us about this challenge in his career. I want to register my special thanks to Prof. Dr. Bruno Martinis from the Department of Chemistry of the Faculty of Philosophy, Sciences and Letters of Ribeirão Preto, University of São Paulo (DQ-FFCLRP-USP) of -, who mediated and made possible the interview for BrJAC of one of the most prominent scientists in the area. In his Point of View, Federal Criminal Expert Marcus Andrade tells us about the complexity of forensic chemical analysis of works of art. The analysis of the surface of a painting requires, besides the historical study of the piece, the physical-chemical characterization of its components through an interesting combination of non-destructive analytical techniques such as microscopy, X-ray fluorescence, infrared spectroscopy, among others, which are powerful tools in the process of authenticating a work of art. Nevertheless, the art market, due to the high added value, has attracted organized crime in money laundering in cases of active and passive corruption. Prof. Dr. Jesus Antônio Velho, Federal Criminal Expert and lecturer at the DQ-FFCLRP-USP, addresses the new trends in analytical chemistry for the examination and interpretation of traces of crimes: the determination of the origin of seized drugs (chemical profile), the investigation of document fraud, and the analysis of the evaluation of works of art. Professor Jesus' letter is the result of his long experience in the field and his exceptional insight into the forensic sciences. The author of several books in the field, his text is a gift to us all. We hope readers will enjoy this special edition of BrJAC. Forensic professionals, students, professors, and researchers seek to contribute to criminal justice more broadly through tireless dedication. When we apply forensic analytical chemistry to a crime scene, more than an expert report, we give voice to the victims, who, through their traces, reveal to us the truth of the facts.

AS CLÁSSICAS HIDRAZONAS COMO REVELADORES DE IMPRESSÕES DIGITAIS: UMA PROPOSTA DE QUÍMICA ORGÂNICA EXPERIMENTAL

CLASSIC HYDRAZONES AS FINGERMARK DEVELOPERS: AN EXPERIMENTAL ORGANIC CHEMISTRY PROPOSAL. Fingermark dusting powders are an important tool of forensic practitioners, being a first-choice process for most crime scene investigators. The development of new products is of utmost importance for forensic science. Hydrazones comprise compounds derived from ketones or aldehydes in reaction with hydrazines. These reactions are widely studied in organic chemistry because of the versatility of these compounds in organic synthesis. The study of these reactions leads to the understanding of the nucleophilicity of hydrazines, as well as the electrophilicity of aldehydes and ketones. The present work presents one proposal of experimental organic chemistry, aiming at a new application of this classic class of organic substances in forensic chemistry, specifically as a developer of latent fingermarks due to the variations of the color of the compounds, with spectra ranging in a range from 250 to 500 nm. These compounds were identified by Infrared Spectroscopy, Ultraviolet-Visible Spectroscopy and Mass Spectrometry. The development on glass surfaces demonstrated the potential application of these compounds in everyday life situations.

Identification of selected fire accelerants from different matrices in forensic samples by using ATR-FTIR

Forensic Science is the application of all the Sciences, to prove or disapprove a test or a fact to corelate the suspect with the victim and the scene of crime, for the truthful execution of trails in the court of law. Forensic chemistry deals with all the chemicals used in an illegal act for the execution of loss of property. Fire accelerants are the liquid, gas or solids which are used for the acceleration of fire, ignited willingly by an arsonist for causing a loss of property to a targeted individual. To confirm an arson and verify whether a fire was intentionally started or not, it is typically necessary to find relevant forensic evidence. Determining the existence of an accelerant is crucial for forensic reasons during the investigation. An accelerant is a material, more precisely a typical ignitable liquid, that has been purposefully added to the scene of a suspicious fire in order to promote the spread of fire. In this study 4 fire accelerant and 6 mixtures of fire accelerant has been used over cotton and nylon cloth pieces.In this study 40 were analysed using Attenuated Total Reflectance-Fourier Transform Infraredfor the determination of the presence of accelerant after burning. The peaks appeared similar for all the fire accelerants, which indicated the presence of similar functional groups in the fire accelerants.

COVID-19 pandemic and alcohol use patterns in Moscow population: forensic aspects

The presents an analysis of the trend of the postmortem ethanol tests in biological samples obtained from the deceased in Moscow in April-May 2019 and 2020. In total, 7110 reports of forensic chemistry studies were examined; all cases were classified by the age of the deceased, following the modern generational theory to study patterns of alcohol consumption in these age groups and the impact of the COVID-19 pandemic. Stable patterns of alcoholic behavior were revealed in the groups of the deceased. It was shown that, on average, every 3rd representative of Generations «X» and «Y» consumes alcohol shortly before death; the highest average blood ethanol levels were found in representatives of Generations «Y» and «X». The number of positive ethanol test results increased in April-May 2020 among males of the baby boom and Generation «X» compared to the same period in 2019. The patterns identified can be used to further study the contribution of alcohol consumption to mortality.

Theoretical and methodological model of criminalistics and its new directions

This research paper purpose is to find out tendencies of development of criminalistics in globalized world, define its borders, forecast emergence of new directions and to characterize them.
 Theoretical and methodological model of criminalistics is studied, tendencies and specifics of formation of criminalistics in modern conditions are traced.
 Formation of internal structure of criminalistics (its system) is considered, connection with other sciences (natural sciences, humanities, social, formal) is determined, relationship with forensic sciences (forensicmedicine, forensic toxicology, forensic psychology, forensic chemistry, etc.) and forensic expertology is established. Attention is drawn to the orientation of the forensic vector of Ukraine to a single forensic European space. Necessity of creating a new section in the structure of criminology, namely: forensic strategy is substantiated.
 Origin specifics, formation and development of new branches (directions) of criminology are considered: competitive, judicial, medical, genotypic, aerospace, computer (digital) and nuclear ones. Necessity of using forensic knowledge by different parties in criminal proceedings both in while of pretrial investigation and in legal proceedings is argued. The subjects of specific expertise application of forensic knowledge should be not only the investigator, but prosecutor, investigating judge, interrogator, detective, judge, lawyer.
 Emergence of new branches of criminology is associated with scientific and technological progress, the emergence of new technologies, the need to work with specific traces and complexity of collecting and examining evidence. Special attention is paid to development and formation of medical, digital and nuclear forensics.

Rapid, presumptive identification of seed-based toxins using direct analysis in real time mass spectrometry (DART-MS) and its variants

Detection of seed-based toxins is a need for forensic chemists when suspected poisonings occur. The evidence that is found is often physically unidentifiable, as the seeds are mashed to extract the toxin. This work investigates potential strategies for rapid detection of seed-based toxins and seed mashes containing these toxins using chemical signatures obtained by direct analysis in real time mass spectrometry (DART-MS). Seven toxins (digoxin, digitoxin, hypaconitine, hyoscyamine, lanatoside, oleandrin, and scopolamine) and six seeds containing these toxins were studied. While detection of four of the toxins was readily attainable, detection of digoxin, digitoxin, and lanatoside was hindered by the inability to thermally desorb these larger compounds under normal operating conditions. The use of DART-MS variants capable of higher desorption temperatures (thermal desorption (TD)-DART-MS and infrared thermal desorption (IRTD)-DART-MS) enabled detection of these compounds. Detection of toxins from direct analysis of seed mashes and methanolic seed mash extracts was found to be compound and technique dependent. Principal component analysis (PCA) of generated mass spectra enabled differentiation of seed species, even in cases where the toxins were undetectable.

Use of voltammetric and chemometric tools to develop a sensor in forensic chemistry

The large number of drug seizures has required the development of electrochemical sensors and new analytical techniques involving portable sensors. Here, we have studied cocaine hydrochloride oxy-reduction on the surface of carbon paste electrodes chemically modified with [VIIO(salen)], and we have evaluated these electrodes as voltammetric sensors for forensic purposes. The modified working electrode for cocaine hydrochloride analysis presented the sensitivity was 1.2 µmol.L−1, and the mean limits of detection and quantification were 0.31 and 1.03 µmol.L−1, respectively. As for the possible interferents, the investigated analytes exhibited similar electrochemical activity, with different sensitivities. Supervised classification of the data for the detection of analytes by the SIMCA chemometric method revealed that the voltammetric methodology predicted cocaine in real samples seized by the police more effectively than the other analytes. Thus, the developed voltammetric sensor has potential use in forensic investigations.

Toward a common language for quality issues in forensic science

AbstractThe call for transparency with regards to the disclosure of errors in forensic science has permeated dialogues within the field, the legal arena and the public domain. While the challenges of meeting this need have been debated, no consistently accepted approach to recording or disclosing critical issues in forensic science has been developed. Part of the solution may lie in the quality system structures already present in forensic service providers world‐wide. However, while quality systems themselves may be standardized, the language used within them is not. We argue that the development of a common language for quality issues in forensic science may provide the key to unlocking this crucial information to support collaboration, continuous improvement, and the fundamental understanding of “error” in forensic science.This article is categorized under: Forensic Chemistry and Trace Evidence > Trace Evidence Jurisprudence and Regulatory Oversight > Communication Across Science and Law Jurisprudence and Regulatory Oversight > Interdisciplinary Collaboration Forensic Chemistry and Trace Evidence > Presentation and Evaluation of Forensic Science Output

Elemental Analysis of Tetrahydrocannabinol and Nicotine E-Liquids Related to EVALI.

During the e-cigarette, or vaping, product use-associated lung injury (EVALI) investigation, the U.S. FDA’s Forensic Chemistry Center (FCC) received numerous sample submissions from various states and other sources. Many of these products were linked directly to patients, while others were not; both categories included used and unused products. Elemental analysis using inductively coupled plasma mass spectrometry (ICP-MS) preceded by microwave-assisted decomposition was carried out on the cartridge contents of 65 of these submitted samples. Challenges encountered included limited sample, high sample viscosity, and adhesion, which necessitated sample preparation techniques not commonly used during routine elemental analysis. The elemental concentrations of contaminants including Pb, As, Cd, Cr, Ni, Cu, and Sn in tetrahydrocannabinol (THC) e-liquids associated with EVALI were determined. Nicotine e-liquid samples collected alongside the THC e-liquid samples were analyzed in tandem during method development. Several THC e-liquid samples contained Pb greater than 0.5 μg/g, while others had part per million levels of Ni, Cu, and/or Cr. This study presents the first detailed report of elemental concentrations in multiple THC e-liquid samples including those from informal/illicit sources and also delves into the method considerations needed for testing a viscous, hydrophobic sample matrix in limited quantity.

Research trends in forensic science: A scientometric approach to analyze the content of the INTERPOL reviews

AbstractThe use of forensic evidence has become indispensable in many countries and jurisdictions around the world; however, the dissemination of research advancements does not necessarily directly or easily reach the forensic science community. Reports from the INTERPOL International Forensic Science Managers Symposium outline major areas that are of interest to forensic practitioners across the INTERPOL member countries. The information contained in the INTERPOL reports is extensive but can be challenging to process. The purpose of this research is to provide a comprehensive overview of the evolution of trends within the INTERPOL reports over an 18 year period. References relating to 10 evidence types retrieved from the 14th to 19th INTERPOL IFSMS reports (2004–2019) were processed and compared with data exports from the citation database Scopus covering the same evidence types. The results from this work are summarized by investigating the relationships between the 10 evidence types. To explore the outputs a user‐friendly R‐Shiny application was developed and is freely available at: https://uod.ac.uk/lrcfsinterpolreportsexplorer.This article is categorized under: Forensic Chemistry and Trace Evidence > Trace Evidence