Forensic Sci., Volume 5, Issue 2 (June 2025) – 7 articles

Background: Chemical odor profiling within forensic entomology is an emerging tool given its potential for species identification and larval aging and its ability to identify decomposition stages. A volatile analysis of larval masses across species of distinctive developmental stages was carried out with extraction techniques to identify odor signatures. However, it is unknown how larval sample handling (i.e., live samples in research vs. hot-water-killed samples in casework) affects odor signatures or the possibility of obtaining relevant volatiles from a single larva. Method: This study utilized solid-phase microextraction (SPME) with gas chromatography–mass spectrometry (GC/MS) for the analysis of odor volatiles emanating from single larval samples of Cochliomyia macellaria. Fifty (50) larvae (25 live; 25 boiled) were analyzed. Results: The SPME-GC/MS method allowed for odor volatile detection from a single maggot regardless of the sample handling group. The main compounds identified across both groups included those previously reported as emanating from larvae and decomposition substrates. When comparing treatments, the boiled larval samples had a 6-fold decrease in compound abundance compared to the live samples. The identified odor volatiles observed in the hot-water-killed treatment group included indole, p-cresol, and phenol. Conclusions: These results suggest that the handling technique impacts odor detection. Additionally, the heterocyclic aromatics and alcohols identified in the boiled samples are potentially odor markers of a higher intrinsic nature to the maggot rather than a cross-transfer from the decomposition substrate given their survival post elevated temperature treatment. This work shows the plausibility of carrying out an odor analysis of a single maggot following both common research and casework handling practices. Full article

Background: The COVID-19 pandemic significantly disrupted forensic science, exposing vulnerabilities and introducing unprecedented challenges. Five years later, its impact persists, necessitating ongoing adaptations in forensic practice. This study examines key transformations, persistent issues, and emerging challenges in forensic science post-pandemic. Methods: A critical analysis of forensic science’s response to the pandemic was conducted, focusing on operational disruptions, methodological advancements, educational shifts, and technological integration. Results: Forensic operations faced delays due to case backlogs, restricted in-person work, and postponed court proceedings. Forensic pathology evolved with increased reliance on molecular autopsy techniques to clarify COVID-19-related deaths. Educational methods shifted toward virtual learning, prompting discussions on standardized digital training. Additionally, artificial intelligence and automation gained prominence in forensic investigations, enhancing crime scene analysis and predictive modeling. Discussion: While forensic science demonstrated adaptability, challenges remain in international collaboration, resource distribution, and professional training. The pandemic accelerated technological integration but also raised ethical and procedural concerns, particularly regarding AI applications in legal contexts. Virtual learning innovations necessitate further development to ensure competency in forensic training. Conclusions: Forensic science continues to evolve in response to post-pandemic realities. Addressing gaps in cooperation, technology implementation, and training will be crucial to strengthening the field. By assessing these changes, this study underscores forensic science’s resilience and adaptability, offering insights into its future trajectory amid ongoing challenges. Full article

Background: Accurately determining the post mortem interval (PMI) is critical in forensic investigations to reconstruct the sequence of events leading up to and following death. Traditional methods (e.g., observing livor mortis, rigor mortis, and using temperature-based models) have limitations due to their empirical nature and susceptibility to environmental variables. The objective of this study was to assess the potential of a novel portable device, the Fisic Medimate™ system, for estimating PMI through the analysis of the potassium/sodium (K+/Na+) ratio in vitreous humor. Method: Vitreous humor samples were collected from pigs at various intervals up to 44.5 hours post-mortem. These samples were analyzed using the Fisic Medimate™ system to determine the K+/Na+ ratio. The analysis was conducted at different time points to establish a relationship between the K+/Na+ ratio and PMI. Results: The results indicated a log-linear relationship between the K+/Na+ ratio and PMI for periods up to 31 hours, with normal residuals. This relationship was observed across all samples, suggesting that the method provides reliable and consistent data. Conclusions: This method offers a rapid and portable solution for PMI determination, providing valuable data within minutes directly at the crime scene. While these findings suggest potential for on-site forensic applications, further validation under real-world conditions is required to confirm its broader applicability. Full article

Background: In forensic investigations, the postmortem interval (PMI) is still mainly determined using pathological analysis. There have been many scientific efforts to identify alternative methods of PMI determination, which may be applied to future forensic practices. Methods: Considering the ethical implications and the availability of tissue samples for PMI experiments, we used human blood samples stored at three temperatures to mimic different environmental conditions, testing them over a period of 10 days post-sampling. These samples were biochemically tested for specific blood biomarkers, glucose (Glu) and lactic acid (Lac), to determine their potential as PMI biomarkers. Then, a mixed-effect mathematical model was applied to the data related to time- and temperature-dependent concentration changes of both biomarkers followed by additional computer-simulated models to refine the PMI estimates based on each of the biomarker concentration changes. Results: Herein, we present this alternative method of PMI estimation based on the biochemical testing of blood samples that could potentially be collected at a crime scene using biochemical blood biomarkers Glu and Lac, which are mathematically modelled and refined with time- and temperature concentration changes. Conclusions: While there is still much forensic science required to validate any alternative PMI methods, this study shows that there are other cross-disciplinary methods of PMI determination that warrant further exploration. Full article

Contemporary human preservation technologies aim to preserve the structure of the body—and especially the brain—after legal death. Although it has not yet been demonstrated, some believe that this may act as a bridge to future medical technologies that could allow for the recovery of life, if this ever becomes feasible and humane. However, current death investigation practices impose two significant obstacles to high-quality preservation. The first and most common is ischemic delay—the period between legal death and initiation of preservation while the death is investigated, during which brain tissue progressively degrades. The second is involuntary autopsy, where tissue disruption can severely compromise preservation quality. Through analysis of legal precedents and the ethical principles of bodily autonomy, non-discrimination, and potential preservation of life, we argue that individuals should be allowed a way to prevent both ischemic delay and autopsy from affecting the quality of their preservation. We explore potential avenues to implement a right to immediate preservation, including administrative, legislative, and judicial approaches, aimed at balancing this right with the societal interest in performing death investigations. This narrative review has implications for individual autonomy, public policy, and the legal framework surrounding death investigation in the context of emerging preservation technologies. Full article

Background: The main objective of this study was to carry out an online questionnaire in order to assess dentists’ knowledge and perception of dental materials submitted to high temperatures, helping to clarify and raise awareness of possible gaps in the area of forensic dentistry, especially in human identification. Results: Out of a total of 272 respondents, there was a greater influx of responses from countries such as Portugal and Brazil, the majority being female (66.3%), with an average age of 39 years. Most dentists consider complete clinical records to be extremely important. In addition, professionals with less experience provide fewer models in releasing their clinical records. In the case of dental materials, dentists consider composite resin and glass ionomers to be more susceptible to changes in shape and colour, while amalgam is considered the most stable, followed by ceramic and metal-ceramic crowns. On the other hand, dentin is considered more susceptible to colour changes than enamel. Enamel is seen by most professionals as resistant, undergoing few changes in shape at high temperatures. Conclusions: The opinion of the surveyed dentists on this subject is broadly in line with the existing literature. The only observed differences were related to exposure time and enamel resistance, since they assume that enamel is more resistant, and dentin is more vulnerable. Full article