Forensic Laboratories Research Articles

The effects of F-500 Encapsulator Agent on canine alerts and laboratory analysis using passive headspace concentration and gas chromatography-mass spectrometry

F-500 Encapsulator Agent (EA) is a fire suppression agent that is an alternative to traditional firefighting foams. It is marketed as having the capability to act on all four parts of the fire tetrahedron as well as being environmentally friendly and non-toxic. An internal survey of the use of F-500 EA by fire departments encountered by the Bureau of Alcohol, Tobacco, Firearms and Explosives (ATF) ignitable liquid detection canine (ILDC) handlers in 2022 showed that this product is not yet in widespread use across the country, but where it has been implemented, it is frequently utilized on a variety of types of fires. Additional agencies are researching the product to determine if it should be adopted. As this product appears to be growing in popularity, it is important to understand whether the use of the product would affect a canine’s ability to detect ignitable liquids or a forensic laboratory’s ability to identify the presence of an ignitable liquid. Burned wood and burned carpet, two commonly encountered substrates, were spiked with gasoline or a heavy petroleum distillate (HPD) and F-500 EA was applied. At various time intervals, ILDC teams surveyed the samples and laboratory analysis was conducted. Results showed that the presence of F-500 EA can negatively affect canine alerts and the laboratory’s ability to identify ignitable liquids.

Hungarian legislation regarding implementing a forensic DNA elimination database

The inception of forensic DNA elimination database represents a pivotal advancement in forensic science, aiming to streamline the process of distinguishing between DNA found at crime scenes and that of individuals involved in the investigation process, such as law enforcement personnel and forensic lab staff. In subsequent phases, once familiarity with the database is achieved by its administrators and other stakeholders, and they have accrued sufficient experience, the possibility of expanding the database to encompass first responders—including firefighters, paramedics, emergency medical technicians, and other emergency services personnel—can be contemplated. Key challenges in managing these databases encompass the grounds for collecting samples, ensuring the integrity of both samples and profiles, along with the duration of retention, access to the database, and the protocols to follow when a match is found in the database. This paper outlines the conceptual and detailed legislative framework in Hungary, where the forensic DNA elimination database was introduced in 2022.

Desorption Electrospray Ionization Mass Spectrometry Imaging of Powder-Treated Fingermarks on Forensic Gelatin Lifters and its Application for Separating Overlapping Fingermarks.

Fingermarks are frequently collected at crime scenes by using gelatin lifters for preservation and transport of the marks to a forensic laboratory for inspection. The gelatin lifters preserve both the imprint of the fingermark pattern necessary for identification purposes and the chemical residue of the mark potentially useful for profiling the person who left the fingermark. The fingermark patterns are traditionally recorded using photography/optical imaging, but methods for chemical analysis of fingermark residues on gelatin lifters are scarce. Here we report the first method for the chemical analysis of fingermarks on gelatin lifters using desorption electrospray ionization mass spectrometry (DESI-MS) imaging. The imaging can be done directly on the gelatin support without any sample preparation, supporting immediate operational use of the method for fingermarks collected at crime scenes. Operational use of the method is further supported by successful chemical imaging of fingermarks enhanced by traditional dusting with forensic powders and lifted off different surfaces (glass, stainless steel, painted aluminum, polystyrene, cardboard, and plastic) as well as fingermarks lifted multiple times. We also demonstrate that the present method can be used to visually separate natural overlapping powder-treated fingermarks, and the chemical composition of the fingermarks can be analyzed on the gelatin support by DESI-MS/MS. The presented method has potential for integration into the traditional workflow for fingermark analysis, and will allow more fingermarks collected at crime scenes to be evaluated both visually and chemically.

Review of SNP assays for disaster victim identification: Cost, time, and performance information for decision-makers.

In mass disaster events, forensic DNA laboratories may be called upon to quickly pivot their operations toward identifying bodies and reuniting remains with family members. Ideally, laboratories have considered this possibility in advance and have a plan in place. Compared with traditional short tandem repeat (STR) typing, single nucleotide polymorphisms (SNPs) may be better suited to these disaster victim identification (DVI) scenarios due to their small genomic target size, resulting in an improved success rate in degraded DNA samples. As the landscape of technology has shifted toward DNA sequencing, many forensic laboratories now have benchtop instruments available for massively parallel sequencing (MPS), facilitating this operational pivot from routine forensic STR casework to DVI SNP typing. Herein, we present the commercially available SNP sequencing assays amenable to DVI, we use data simulations to explore the potential for kinship prediction from SNP panels of varying sizes, and we give an example DVI scenario as context for presenting the matrix of considerations: kinship predictive potential, cost, and throughput of current SNP assay options. This information is intended to assist laboratories in choosing a SNP system for disaster preparedness.

El proceso de gestión de la calidad en los laboratorios forenses: un avance global hacia una interpretación local

This article aims to describe the most relevant aspects of accreditation applied to forensic laboratories and forensic inspection activities. It intends to clarify the use of concepts found in the definition of accreditation, as well as understanding the meaning of this tool in forensic laboratories and forensic inspection activities, identifying critical elements in their performance. Thus, the article explains how accreditation is implemented in forensic laboratories and in forensic inspection activities in Mexico. Finally, it presents some topics regarding evident improvements in the expert activity and some analytic data to assess those advances.

Advancements in differentiation between sperm cells and epithelial cells for efficient forensic DNA analysis in sexual assault cases.

Most of the sexual assault casework samples are of mixed sources. Forensic DNA laboratories are always in the requirement of a precise technique for the efficient separation of sperm and non-sperm DNA from mixed samples. Since the introduction of the differential extraction technique in 1985, it has seen significant advancements in the form of either chemicals used or modification of incubation times. Several automated and semi-automated techniques have also adopted the fundamentals of conventional differential extraction techniques. However, lengthy incubation, several manual steps, and carryover over non-sperm material in sperm fraction are some of the major limitations of this technique. Advanced cell separation techniques have shown huge promise in separating sperm cells from a mixture based on their size, shape, composition, and membrane structure and antigens present on sperm membranes. Such advanced techniques such as DEParray, ADE, FACS, LCM, HOT and their respective pros and cons have been discussed in this article. As current-day forensic techniques should be as per the line of Olympic slogan i.e., faster, higher, stronger, the advanced cell separation techniques show a huge potential to be implemented in the casework samples.

Forensic science in the justice system: learnings from the Queensland DNA inquiry

ABSTRACT The Queensland DNA Inquiry, conducted by Walter Sofronoff KC, unearthed substantial deficiencies in forensic DNA practices, highlighting the need for rigorous scientific standards and improved management within forensic laboratories. The inquiry’s final report made 123 recommendations to overhaul these practices, prompting the Queensland Government to pledge over $95 million towards restructuring forensic services. This paper reflects on a workshop convened by the Victorian Chapter of the Australian Academy of Forensic Sciences, which explored the implications of these recommendations for other jurisdictions. The workshop facilitated a rich dialogue among legal, scientific, and government sectors, emphasizing the necessity of a holistic approach to forensic science within the justice system. It underscored the importance of impartiality in forensic services, the need for fit-for-purpose operational frameworks, and robust quality management to uphold the integrity of forensic evidence. By examining these themes, the paper contributes to ongoing discussions about enhancing forensic science’s role in ensuring justice and underscores the potential for significant reforms catalysed by the inquiry’s findings.

Fire fighters and mass spectrometry: from the world of combustion to the molecular ion

Abstract The background and current studies in the area of fire investigation at the Turin Fire Department’s Forensic Laboratory. It is uncommon to find an investigation facility, and even less often within fire brigade headquarters, that uses GC-MS and GC-TOF extensively to look for accelerants. During 16 years of intense effort, the Turin Fire Department in Italy accomplished various research projects on the identification of flame accelerants and more in fire residues. This collaborative effort between academics and firefighters is unique. It is based on the perspectives of individuals who often fight fires before going on to investigation. The article will outline the study that was done, explain how advances in instrumentation have produced ever-better outcomes and the next steps in the foreseeable future.

Comparative DNA profiling of conceptus parts in paternity disputes and rape investigations: a case study

Forensic laboratories frequently receive cases related to abortion, particularly in the context of paternity disputes and rape crimes. However, the focus has traditionally been on the foetus, while the placenta and its associated components, which start development after one month and mature within three months, are often overlooked. This study represents the comparison of DNA profiling from various parts of the aborted conceptus, including the placenta (foetal side), placenta (maternal side), umbilical cord, and foetus. The results have produced consistent and expected profiles but with meticulous foetal tissue processing. Due to the significant presence of maternal blood in these components, a rigorous washing procedure for the aborted foetal material is imperative before DNA extraction can be carried out. The generated profiles emphasize the equal forensic utility of different conceptus components, challenging the conventional focus on the foetus alone. This study paves the way for collecting and processing of various developed parts of the conceptus for DNA profiling as required by the specific case scenarios.

A detailed study on human height estimation model that combines video surveillance systems with 3D laser scanning.

The increase of video surveillance systems has highlighted the interest in forensic anthropometric analysis of subjects who commit crimes and are captured by cameras during their criminal activities. There are different methodologies for human height estimation. Forensic researchers developed a methodological approach that allows the height of a subject to be estimated through a combined model of 3D laser scanning acquisition and video images acquired by video surveillance systems. The proposed study had highlighted three limits: not assessments had been made for image correction to limit the distortion effect, the method had been tested by only one laboratory and probably height assessment was dependent on the ergonomics. To overcome these limitations, in this paper the analysis was repeated by correcting the images to compare the new results obtained with the previous ones. Furthermore, the same methodological approach was applied by estimating the height of a mannequin, to limit the ergonomic effects, and proposing the same study to three different forensic laboratories to compare the results. The presented study demonstrates the reliability and repeatability of the system, as the results obtained by the three laboratories are very similar. They have obtained the same trend and the maximum estimate distance is approximately 6 cm. Furthermore, it has showed that the accuracy of results is dependent on image correction, which has little impact (approximately 1 cm more accurate on the corrected frame than the normal frame) on the height evaluation and they are not dependent to the ergonomics of the subject captured.

Identification of oral bacteria as a new forensic tool for saliva detection

Body fluid detection is an important component in the toolbox of forensic scientists, with saliva playing a particularly critical role in forensic evidence. Given that each body fluid possesses a distinct microbiome, the identification of body fluid based on specific representatives of the microbiota presents an appealing approach for forensic applications. In this study, we have developed a real-time polymerase chain reaction (RT-PCR)-based method for the precise identification of saliva, focusing on three bacteria highly associated with saliva but not with other tested body fluids -Porphyromonas gingivalis, Fusobacterium nucleatum, and Streptococcus salivarius. The inclusion of these three bacterial species enhances the accuracy of detection and reinforces validation. Notably, specific identification of saliva was achievable even at low concentrations where Phadebas, a commonly used method for saliva detection, proved ineffective. Importantly, bacteria-based saliva detection utilizes DNA generated for small tandem repeats (STR) profiling, facilitating seamless integration into forensic laboratories and optimizing DNA sample utilization. This study collectively proposes an effective bacterial DNA-based approach for saliva identification, demonstrating promising potential for forensic applications.

Differentiation and classification of human head hair via spectroscopic analysis, data fusion, and neural networks

BackgroundAttenuated Total Reflectance – Fourier Transform Infrared (ATR-FTIR) spectroscopy and UV–visible microspectrophotometry (MSP) are common in forensic labs. These form a non-destructive method to classify hairs from different individuals using chemometrics. ResultsHair samples were collected from 14 individuals and analyzed. High-level data fusion and neural networks exhibited 100% classification accuracy. SignificanceThe forensic analysis of hair currently involves microscopic and genetic analysis. However, chemical techniques and machine learning can successfully classify hair.

N,N-dimethylpentylone poisoning: Clinical manifestations, analytical detection, and metabolic characterization

IntroductionThe proliferation of new psychoactive substances (NPS) poses a significant challenge to clinical and forensic toxicology laboratories. N,N-dimethylpentylone, a novel synthetic cathinone, has emerged as a public health concern. The aims of this study are to describe the clinical presentation of N,N-dimethylpentylone poisoning, to describe detection methods, and to deduce its metabolic pathways. MethodsClinical data was collected and reviewed retrospectively from patients with confirmed N,N-dimethylpentylone exposure. Liquid chromatography-tandem mass spectrometry (LC-MS/MS) was used to identify N,N-dimethylpentylone and its metabolites in urine samples. The metabolic pathway was characterised by comparison of the detected substances with reference standards. ResultsEight cases were included in the case series. Seven different metabolites of N,N-dimethylpentylone were identified in in vivo patient urine samples, where the two major metabolic pathways were proposed to be opening of the 5-membered ring and reduction of carboxide. All patients presented with neuropsychiatric and/or cardiovascular symptoms. Co-ingestion with other substances was reported in all cases. One patient requiring intensive care was described in detail. All patients eventually recovered. The analytical method allowed the simultaneous identification of N,N-dimethylpentylone, pentylone and bisdesmethyl-N,N-dimethylpentylone, as well as other drugs of abuse in patient samples. ConclusionN,N-dimethylpentylone appears to be less potent than its metabolite pentylone. Co-ingestion with other drugs of abuse is common. Poisoning cases have neuropsychiatric and cardiovascular manifestations. An updated and comprehensive laboratory method is needed for its detection.

Sequencing-induced artefacts in NGS STR data

Significant progress has been made in recent years in the development of techniques for Next Generation Sequencing (NGS), or Massively Parallel Sequencing (MPS), of forensically relevant short tandem repeat (STR) loci. However, as these technologies are investigated and adopted by forensic laboratories, new challenges unfold that require further scrutiny. In the analysis of DNA profiles generated using the MiSeq FGx sequencing system, we have observed noise sequences with relatively high readcounts that are challenging to distinguish from genuine alleles. These high read count noise sequences appear as allele sequences with one or a few substituted bases compared to a known allele sequence within the profile.An examination of ForenSeq DNA Signature Prep Kit STR noise sequences revealed that the substituted base of a parent allele can align to the same position on the sequence across noise sequences. This suggests that these substitution events occur at specific positions within the amplicon, resulting in multiple noise reads with substitutions at the same position. Mapping of the noise events onto the original raw read positions revealed a high number of events, or “noise spikes”, occurring atspecific positions within a given sequencing run. These noise spikes affected reads across the entire run, agnostic of locus or sample, while the position, occurrence, and amplitude of the spikes differed across runs. The majority of noise sequences with high read counts in a DNA profile were generated from base changes at these spike positions, and could be classified as “noise spike artefacts”.In this paper we present evidence of the noise spike artefacts and their genesis during the sequencing process in the sequencing-by-synthesis (SBS) cycles, as well as the methods developed to detect them. The information and methods will assist laboratories with detecting noise spikes in MiSeq FGx sequencing runs, differentiating authentic allele sequences from noise spike artefacts, and developing protocols for analyst review and handling of MiSeq FGx data.

Liquid Chromatography-Mass Spectrometry: A Review

The analytical technique known as liquid chromatography-mass spectrometry is incredibly precise and sensitive. It's a really powerful tool. Detection, identification, and mass determination of components in the presence of additional components are carried out by mass spectrometry using sample eluents from liquid chromatography and mass spectrometry. Liquid chromatography is used to identify pharmaceutical medication components, intermediates, and related compounds for both quantitative and qualitative applications. Liquid chromatography is mostly used in-vitro dissolution, bioequivalence, bioavailability, and metabolite research. Liquid chromatography mass spectrometry is also used in forensic labs, agrochemical firms, fundamental research, and the food industry. Applications, instrumentation, and the liquid chromatography-mass spectrometry principle are covered in this review. Keywords: Liquid Chromatography, Mass Spectrometry, High Performance Liquid Chromatography, Bioequivalence, Metabolite research.

Detection of the benzodiazepine bromazolam by liquid chromatography with quadrupole time of flight mass spectrometry in postmortem toxicology casework and prevalence in Indiana (2023).

For the past 60 years, benzodiazepines such as chlordiazepoxide, diazepam, and alprazolam have been used as pharmaceutical medications for the treatment of myriad conditions including anxiety, seizures, and insomnia. In more recent years, novel benzodiazepine derivatives have emerged as illicit substances in powders and counterfeit tablets on the illicit drug market. In 2016, bromazolam, a brominated derivative of alprazolam, emerged on the illicit drug market in Europe, but the substance was not reported in the USA until 2019-2020. In this study, we report the emergence and subsequent prevalence of bromazolam in postmortem blood in the state of Indiana during 2023. Analysis was completed by a solvent protein precipitation extraction with acetonitrile and detection by liquid chromatography with quadrupole time of flight mass spectrometry. During 2023, bromazolam was detected in 94 cases across 25 counties in Indiana. It was never the sole substance detected and was commonly detected alongside fentanyl (83 cases), norfentanyl (77 cases), 4-anilino-N-phenethylpiperidine (76 cases), acetylfentanyl (49 cases), methamphetamine (32 cases), naloxone (25 cases), 11-nor-9-carboxy-tetrahydrocannabinol (24 cases), and benzoylecgonine (20 cases). After official query with the Indiana Department of Health, it was found that bromazolam was specifically included in the cause of death certification in 31 fatalities (32.9%). Due to the scarcity of information regarding this novel benzodiazepine derivative in postmortem toxicology and its involvement in fatalities, it is important that forensic toxicology laboratories consider adding bromazolam to their comprehensive scope of analysis.

Seized drug reporting of NPS helps to guide regional toxicological practice: A 17 month review between 2022 and 2023.

Novel psychoactive substances (NPS) are everchanging and plague forensic laboratories who must identify an unending variety of emerging substances and evolve current methodologies to detect these substances. Identifying potential regional NPS targets and timely examining trends in seized drug data could help mitigate the burden laboratories face. Over 17 months, NPS seized drug data were processed and categorized from three laboratories located across the United States to determine any NPS regional similarities and prevalent NPS drug categories: the South Carolina Law Enforcement Division (SLED), the Sedgwick County Regional Forensic Science Center (SCRFSC), and the Orange County Crime Laboratory (OCCL). Seized drug materials, including pills, powders, and plant material, were primarily analyzed for NPS via gas chromatography-mass spectrometry and Fourier transform infrared spectroscopy. From June 2022 to October 2023, 1940 NPS seized drug identifications were reported by these laboratories with 63 different NPS reported. Novel synthetic opioids (NSO) were the most prevalent NPS class across all three laboratories (55%), with fluorofentanyl accounting for 74% of NSO identifications. This is unsurprising given the fentanyl epidemic in the United States. Furthermore, these data highlighted varying regional NPS seized drug trends: eutylone, a synthetic cathinone, was one of the most frequently identified NPS in SLED, SCRFSC observed the most diverse set of synthetic cannabinoids, and OCCL observed an increased prevalence in the designer benzodiazepine, bromazolam. NPS scope recommendations are a valuable resource for forensic laboratories; however, most focus on a national perspective. Timely analysis and reporting of NPS seized drug data may help to develop regional NPS scope recommendations laboratories may employ.

An Extensive Analysis of Contemporary Studies Forensics Sciences in India

: Forensic science in India has evolved over 100 years, with the first official laboratory being the Calcutta Forensic Science Laboratory in Kolkata founded in 1952. Modernization has led to the establishment of numerous central, state, and regional forensic laboratories and advancements in technology such as DNA profiling, pathology, forensic toxicology, and forensic anthropology. As the need for forensic education in India increases, educational institutions and universities have started offering forensic science as a subject. India has collaborated with international forensic organizations to stay updated on global developments. Contemporary studies in forensic sciences are crucial for adapting to technological advancements, addressing emerging crimes, improving DNA analysis, promoting interdisciplinary approaches, and maintaining quality assurance and standards. Forensic science plays a significant role in the humanitarian efforts, including the identification of missing people and victims of mass disasters. Advanced imaging techniques are crucial in forensic investigations. Indian forensic science education is divided into undergraduate and postgraduate programs, offering bachelor's degrees and specialized courses in areas like forensic toxicology, DNA analysis, and digital forensics.

Utilizing derivatizing agents for the differentiation of cannabinoid isomers in complex food, beverage and personal-care product matrices by ambient ionization mass spectrometry

Recent legalization and decriminalization of marijuana at the state level has not only contributed to a rise in the recreational use of Cannabis sativa, also known simply as Cannabis, but also to an increase in the range of matrices into which cannabinoids derived from it are infused. Traditional methods for analyzing these products, which are typically chromatography-based, are often matrix-dependent and demand time-consuming and resource-intensive sample preparation protocols that are highly nuanced and not readily applicable to multiple matrix types. Furthermore, the differentiation of cannabinoids can be troublesome without implementing lengthy run times to achieve resolution of chromatographic peaks. With complex samples such as edibles, beverages, personal-care products, and plant materials, a method that can be more universally applied to rapidly detect and differentiate between cannabinoids is highly desirable. In this study, foods and personal-care products under the categories of sweets, spreads, condiments/toppings, beverages, oils, and commercial body products were spiked with cannabinoids including Δ9-tetrahydrocannabinol (THC), cannabidiol (CBD), cannabicitran (CBT), and cannabigerol (CBG). Chemical derivatization of the samples with N-methyl-N-(trimethylsilyl)trifluoroacetamide (MSTFA) followed by direct analysis in real time – high-resolution mass spectrometry (DART-HRMS) analysis readily revealed the presence of cannabinoids in the products despite the matrix complexity (i.e., the contributions from matrix-derived peaks did not interfere with the differentiation of cannabinoids). When analyzed under ambient soft ionization conditions, CBT, THC and CBD are indistinguishable because they are isomers with a molecular formula of C21H30O2 and a protonated monoisotopic mass of 315.2324. However, due to the different number of hydroxyl (-OH) groups (zero in CBT, one in THC, and two in CBD) that engage with the derivatizing agent, the cannabinoids are differentiated based on the mass disparities of the protonated adducts formed (m/z 315.2324, 387.2719 and 459.3119 for CBT, THC, and CBD, respectively), which is readily revealed by DART-HRMS. This approach circumvents some of the challenges currently encountered by forensic laboratories in the analysis of highly complex and diverse cannabinoid-infused matrices. The results show proof-of-concept for an approach that can aid in the differentiation of cannabinoid isomers by DART-HRMS that accommodates high matrix diversity and complexity, and demonstrates the potential for the approach to be integrated into current workflows for the forensic analysis of Cannabis-related materials and evidence.

Comparative Gross Architectural Studies on the Skull of Male Chital Deer (Axis axis) and Sambar Deer (Rusa unicolor) as an Aid in Wildlife Forensics

Background: Madhya Pradesh is rich in biodiversity having diversified flora and fauna. But now a days, apart from various threat like loss of habitat poisoning, accident, disease facing wildlife today and poaching remain one of the important causes for fauna declination. poaching remains one of important cause for fauna declination. Poaching of wild animals particularly chital and sambar deer is more for the meat, ornamental and trophy purposes. In forensic laboratory where there is lack of molecular facilities, comparative gross morphological study plays an important role in solving wildlife crime cases. skull is a best material to compare the closely relative species. hence, the study was conducted on comparative gross morphology of 4 male chital and sambar deer skull. Methods: The study was conducted 4 male adult skulls each of chital and sambar deer. The skulls were de-skinned and kept under maceration for a period of one month. The gross morphological differentiating features of dorsal surface, lateral surface, basal surface and nuchal surface were observed and recorded with the help of digital camera. Result: In this study, unique differentiating features were sufficient to distinguish among the skull of male chital and sambar. The facial tuberosity was present caudal to infraorbital foramen, dorsal to the superior third premolar tooth in chital deer, whereas; it was present dorsally the superior first molar tooth in sambar deer. Rostral extremities of nasal bones in skull of male chital deer were notched; however, these were blunt and without notch in the skull of male sambar deer. Incisive (Premaxilla) bone was directed upward in chital deer; whereas, it was directed caudally in case of sambar deer. The present comparative study will provide reliable information for identification of these closely related species specially needed for wildlife forensic cases.