PURPOSE:Hair-root analysis provides information on recent drug exposure, which can serve as a useful complementary approach to urine- and blood-based testing. This study investigated the early-stage incorporation behavior of a model drug into white hair (from 30 min to 72 h after intake). METHODS:Black and white hair specimens were provided from participants after a single oral dose of methoxyphenamine (MOP), a non-regulated analog of methamphetamine. Drug distribution in hair was determined by 1-mm segmental analysis of single-hair specimens using liquid chromatography-tandem mass spectrometry. RESULTS:In white hair, as in black hair, MOP was first detected in the hair bulb region 30 min after intake, and subsequently in the upper dermis zone 1 h after intake. However, marked differences between black and white hair were observed in the subsequent time-course changes in drug distribution. In the hair bulb region, MOP concentrations in white hair began to decrease earlier than in black hair, and the maximum concentrations in white hair were only about one-twentieth to one-tenth of those in black hair. In the upper dermis zone, a gradual decrease in drug concentration was observed only in white hair after 12 h from intake, although the difference attributable to hair color was smaller than that observed in the hair bulb region. CONCLUSIONS:Hair-root analysis is applicable to white hair; however, concentrations of basic drugs are substantially lower than those in black hair. The drug incorporation behavior revealed in this study is crucial for the proper interpretation of hair testing results.
Forensic tissue mechanics has emerged as a promising complementary approach for post-mortem interval (PMI) estimation, particularly for intermediate and later post-mortem phases where temperature-based methods become unreliable. However, human kidney tissue has not yet been systematically investigated within this framework. This study aimed to characterize the rheological properties of human kidney tissue under standardized post-mortem conditions and assess their relationship with PMI and potential confounding factors. Kidney samples from 49 cadavers (36 male, 13 female; mean age 65 ± 16 years; PMI range 42-518 h) were collected during forensic autopsies. Circular cylindrical tissue samples were subjected to oscillatory shear rheometry to determine storage modulus (G'), loss modulus (G"), and complex shear modulus (G*). Histological examination and statistical analyses including univariable and multivariable regression were performed. G' and G* showed significant negative correlations with PMI (G': r = -0.379, p = 0.010; G*: r = -0.374, p = 0.012), indicating progressive post-mortem tissue softening. For the 250-hour PMI threshold, G' yielded a positive likelihood ratio of 9.9 (sensitivity = 35.3%, specificity = 96.4%; cut-off value = 1251 Pa). PMI-related biomechanical changes were independent of age at death, sex, kidney weight, gross renal pathology, and cause of death, suggesting potential diagnostic utility as part of a multi-organ biomechanical framework. Human kidney tissue exhibits characteristic post-mortem biomechanical alterations associated with PMI but no other relevant confounders. The observed rheological changes support kidney biomechanics as a valuable addition to a multi-organ framework for forensic PMI estimation during intermediate and later post-mortem intervals.
DNA interpretation of biological mixtures is arguably one of the most challenging and time-consuming steps in the forensic DNA analysis workflow, often requiring the use of complex end-point mixture deconvolution procedures. This has led the research community to seek out reliable cell separation methods that are capable of isolating different cell types in an attempt to prevent mixtures entirely. A proposed alternative approach to differential extraction is optical trapping, a non-invasive method that utilizes the properties of light to create an optical trap for cell separation and manipulation within a reconstituted sample with minimal preparation. The optical trap is created by tightly focusing a laser beam through an immersion objective on an inverted microscope, where the force applied by the laser captures individual cells or cell clusters. While previous work demonstrated successful isolation and complete, single-source STR profiles by trapping 15 leukocytes or 40 sperm cells in an open droplet format, this work focused on optimizing optical trapping in a closed microfluidic device system as well as demonstrating success in capture and movement of epithelial cells. Using an improved laser and microfluidic device architecture, optical trapping was consistently successful in isolating and obtaining single-source profiles of both spermatozoa and vaginal epithelial cell contributors on a single microfluidic device, not only from simulated sexual assault mixtures but also from postcoital vaginal swabs. These innovations demonstrate the potential for optical trapping in forensic biological samples, and ultimately could reduce labor and time by eliminating mixtures at the beginning of the DNA analysis workflow.
With over 1000 cases now resolved with the help of Forensic Investigative Genetic Genealogy (FIGG), this new tool has been shown to produce investigative leads where traditional DNA testing has not. Because of FIGG's success, state public forensic laboratories have begun to examine considerations for implementing it in-house, including: integrating FIGG into current quality assurance systems, the instrumentation and training needed for SNP profile generation, genealogist training and qualifications, data privacy concerns, and data storage hurdles. This paper discusses a 2023 statewide survey conducted in partnership by Illinois State Police and the University of Illinois Urbana-Champaign's Investigative Technology Exchange. The survey assessed the current use, demand, and potential pathways for FIGG implementation among Illinois law enforcement agencies (LEAs) and medical examiner/coroner (MEC) offices. The goal of the survey was to explore in-state FIGG trends and needs that could be used to assist in statewide implementation initiatives. In total, 132 agencies (28 MECs and 104 LEAs) across 54 Illinois counties were used in the analyses. Of these, 16.5% reported prior FIGG use, with no significant differences by agency type or population density. Regarding implementation models, survey findings suggest that Illinois agencies strongly favor a centralized, state-supported system for FIGG use in investigations, with FIGG conducted at a state-run laboratory. Further, respondents' emphasis on security, standardization, and cost efficiency reinforces the need for a sustainable, state-coordinated FIGG implementation framework. Other findings included the estimated success rate of FIGG in Illinois (76-86%), costs (median of $7500), and the rate of FIGG familiarity (19%).
Semi-synthetic cannabinoids (SSCs) have recently emerged on the new psychoactive substances (NPS) market, alongside the availability of cannabidiol (CBD)-enriched products with low-Δ9-tetrahydrocannabinol (Δ9-THC). SSCs are typically produced by chemical modification of CBD and Δ9-THC, unlike synthetic cannabinoids (SCs), and pose additional challenges for forensic toxicology and public health. The aim of the present study is to provide empirical data on the presence and approximate amounts of SSCs and SCs in low-Δ9-THC products, available online from Italian websites. Twenty-six products, including cannabis flowers, vape-liquids and resins, were purchased between September 2024 and January 2026. Products were analyzed at the Institute of Legal Medicine of Bologna, Italy, by gas chromatrography mass spectrometry (GC-MS) and high-resolution mass spectrometry (HRMS), providing quantitative percentages of Δ9-THC, CBD and approximate amounts of SSCs or SCs. All samples contained CBD (median 7.8%) and Δ9-THC (median 0.4%), including 2 samples with Δ9-THC > 0.6%. H4CBD was the most frequently detected SSC (23.1% of all samples), followed by Δ9-THCP (19.2%) and Δ8-THCP (15.4%). SCs were detected in 4 products, consisting of EDMB-4en-PINACA in 3 cases (11.5% of samples). HRMS enabled confirmation of SSCs when approximated GC-MS amounts exceeded 0.25%. Overall, 92.3% of products were mislabelled. Our results highlight the chemical complexity and widespread mislabelling of legal cannabinoid products circulating on the Italian market. A coordinated response, including improved analytical methods, standardized testing and continued market surveillance, is needed to properly respond to the evolving landscape of SCs and SSCs in consumer products.
It is well established that automotive paintwork is not homogeneous across an entire vehicle. This heterogeneity can be problematic during forensic comparisons. However, the homogeneity of the paint system within a single automotive part has not yet been extensively studied.The homogeneity and intra-variability of the paintwork were assessed for 28 automotive parts. For each part, five to seven paint fragments were examined with microscopy using brightfield, darkfield, crossed polars, and fluorescence. The layer sequence, number of layers, individual layer thickness, and total paint thickness were assessed.In all cases, variations in thickness and/or in the sequence and number of layers were observed within the same automotive part. This was also the case for Original Equipment Manufacturer (OEM) systems, where variations in layer thickness were observed. For plastic parts, the clearcoat was more likely to exhibit the greatest variability. For metal parts, thickness variability was generally more pronounced for the primer surfacer and clearcoat, while the primer (e-coat) remained the most uniform.Automotive parts with repaints/repairs showed a higher variation in total thickness. These results emphasize the importance of collecting multiple reference samples as close as possible to the damaged area.
BACKGROUND:Forensic dental identification relies on the comparison of antemortem (AM) and post-mortem (PM) records. In the absence of restorative features, identification depends on inherent anatomical structures, such as root morphology, for which no standardized descriptive framework exists. OBJECTIVES:To propose a structured, atlas-based radiographic classification of mandibular molar root morphology specifically designed for forensic dental identification, and to evaluate its reproducibility among observers with varying levels of forensic experience. METHODS:A radiographic classification comprising six morphological parameters was applied to 512 molars depicted in 22 panoramic radiographs. Sixteen observers (three forensic odontologists, 13 prosthodontic residents) independently classified all cases. Additional real forensic cases including 56 mandibular molars were evaluated by four forensic odontologists. Inter-observer agreement was assessed using average pairwise agreement, Fleiss' Kappa, and Gwet's AC1 coefficient. RESULTS:Inter-observer agreement ranged from 75% to 91% among experts and 77%-89% among residents. Gwet's AC1 demonstrated substantial to almost perfect agreement (0.62-0.88). Lower agreement was observed in third molars with atypical morphology. In the real forensic cases, inter-rater agreement was 89.1% (Gwet's AC1 = 0.878) and intra-rater agreement was 95.7% (Gwet's AC1 = 0.952). A pairwise AM-PM identification analysis correctly ranked the true match first in 71.4% of cases and within the top two candidates in 100% of cases. CONCLUSIONS:The proposed classification provides a reproducible and standardized framework for describing mandibular molar root morphology in a forensic context. Substantial inter-observer agreement across experience levels, supports its use in AM-PM radiographic comparison and potential future computational applications in automated forensic radiographic comparison.
Authorship verification in social media text is a growing challenge in digital forensics, yet existing stylometric approaches rely on textual features that degrade substantially when reference and questioned texts originate from different communicative contexts. This study investigates whether emoji usage patterns-a pervasive but underexplored dimension of digital communication-can serve as viable stylometric markers for forensic authorship verification. We propose 20 novel emoji-based features organized into six thematic categories and evaluate them on a large-scale dataset of 4697 Reddit authors comprising 1023,826 comments (19.9% emoji-bearing, 325,746 emoji instances across 2604 unique types). Three models-emoji-only (20 features), classic stylometric baseline (27 features), and hybrid (47 features)-are compared across 49 configurations varying profile and test sample sizes from 5 to 500 comments. The emoji-only model achieves a diagonal accuracy range of 55.8-94.9%, the classic model 71.8-96.3%, and the hybrid model 72.4-98.2%, with the hybrid significantly outperforming the classic baseline at moderate sample sizes (concordant on the Holm-corrected McNemar test, the paired t-test, and likelihood-ratio cost at P = 25-100). Crucially, cross-subreddit robustness analysis reveals that emoji features maintain virtually identical accuracy across topical boundaries (Δ = -0.009), whereas classic features suffer a 26.6 %age point degradation-demonstrating that emoji features capture topic-independent authorial behavior resistant to the domain shifts that undermine traditional stylometry. Ablation analysis indicates that the distributional emoji features-corpus-level frequency divergences between authors-contribute the greatest non-redundant information to the hybrid model. Recasting the verification scores as calibrated likelihood ratios yielded well-calibrated forensic evidence, with the hybrid model achieving the lowest empirical cost (Cllr) at profile sizes up to 100 comments. These findings establish emoji-based stylometry as a complementary forensic tool with a distinctive advantage in cross-domain scenarios and provide empirically grounded data sufficiency thresholds for forensic casework.
Animal attacks are a significant and increasingly frequent forensic problem, yet forensic pathological research remains largely confined to the description of individual bite marks and wounds. This narrative review, conducted according to a structured and reproducible methodology informed by the principles of the PRISMA framework, aims to (i) synthesise species-specific lesion patterns and the underlying ethology of the domestic and wild animals most frequently implicated in human attacks, and (ii) propose a structured, probabilistic operational model to support forensic practitioners in the investigation of fatal and non-fatal animal-related injuries. A literature search of PubMed, Scopus, and Web of Science (search terms “animal bite,” “animal attack,” “forensic pathology,” “bite mark analysis,” “animal behavior”) yielded 286 records, of which 43 were retained after screening for relevance to forensic pathology, focusing on canids, suids, equids, and bears. Dogs account for the majority of reported attacks worldwide, whereas wild boars, pigs, equids, and bears are less frequent but increasingly implicated in urban and peri-urban settings. Lesion patterns vary consistently by species, victim age, and circumstances, and are summarised comparatively to support differential attribution. The novelty of the work lies in reframing the interpretative process as a structured diagnostic tool with defined inputs (scene assessment, external examination, autopsy, histology, and genetic/microbiological analysis), explicit decision pathways, and probabilistic outputs, emphasising that species attribution rests on the convergence of multiple independent lines of evidence rather than on any single deterministic finding. Beyond individual casework, the model is positioned as a potential component of a broader surveillance and risk-assessment system: the current absence of centralised, standardised data-collection frameworks and behavioural risk registries limits both forensic validation and public-health prevention. Integrating species-specific ethology and lesion analysis from the scene to the post-mortem examination can improve the accuracy and reproducibility of medico-legal investigations and support evidence collection, prevention, and legal decision-making within a One Health perspective.
This study provides a longitudinal analysis of cocaine seizures in North‑East Italy from 2015 to 2025, integrating forensic toxicological data and clinical indicators to characterize evolving market dynamics. A total of 6301 cocaine‑containing samples were analyzed using validated GC‑MS and GC‑FID methods, enabling high‑resolution monitoring of purity trends and adulteration profiles. Findings reveal a marked and sustained increase in cocaine potency, with mean concentrations rising from approximately 50% to 75%, and a progressive compression of the distribution toward high‑purity values. Low‑purity materials (<50%) nearly disappeared, while high‑potency products (>80%) expanded sharply. Adulteration patterns shifted from widespread dilution to more selective combinations, including the increased use of pharmacologically active agents such as caffeine and procaine. Purity‑adjusted dose‑equivalent calculations indicate a doubling of the potential market impact between the first and last triennium, with a tenfold rise in high‑potency dose equivalents. Parallel analyses of judicial cases involving minors show similar trajectories, suggesting increasing exposure among younger users. Questionnaire‑based clinical data corroborate these trends, documenting a high prevalence of sympathomimetic adverse effects and a growing burden on addiction services. Overall, the findings depict a cocaine market characterized by evolving adulteration patterns and a greater capacity to generate acute and chronic harm. These results underscore the need for strengthened early‑warning systems, integrated forensic-clinical monitoring, and targeted prevention strategies.
Estimating time since death, or Post-Mortem Interval (PMI), is a critical component of forensic veterinary pathology. Although many variables are implicated in the decomposition timescale, environmental temperature and its fluctuations significantly affect its progression and the accuracy of PMI estimates. Accumulated Degree Days (ADDs) assist in PMI determination by summing the daily average environmental temperatures. Biomolecular techniques, especially RNA-based analysis, offer promising applications due to the intrinsic instability of RNA after death. In this study, 54 deceased cats collected from veterinary clinics underwent post-mortem (PM) liver sampling. It was performed in 48 cats after exposure to either an outdoor environment ("in field") or stored at + 4 °C ("refrigerated") for 1, 3, 14 and 28 days (6 cats each time point). The remaining 6 cats were sampled within 1 h of death ("controls"). ADDs were subsequently calculated. Microfluidic electrophoresis was performed on RNA extracts from liver samples, obtaining RNA Integrity Number (RIN) and DV200 (percentage of RNA fragments above 200 nucleotides) values. The degradation of target reference gene mRNAs (RPL17, GAPDH, HMBS) was evaluated using qPCR and ddPCR. A statistically significant reduction (p < 0.05) of RIN, DV200 and RPL17-mRNA levels was observed in "in field" cats within the 51-200 ADDs range, compared to controls. In the "refrigerated" cats, similar degradation patterns were found between 14- and 28-day cats compared to controls (RIN, DV200, and qPCR results on GAPDH-mRNA, p < 0.01). RIN and DV200 appear to be promising parameters for PMI estimation in cats, particularly for distinguishing recent deaths from those exceeding 50 ADDs.
Automatic speaker recognition (ASR) is a method used in forensic speaker comparison (FSC) casework. In FSC cases two voice recordings are compared to make an inference about speaker identity. When employing ASR for this task, the case audio is compared by software, resulting in a case score. This case score needs to be converted (calibrated) to a likelihood ratio, the formal metric of strength of evidence. An LR calculation set (calibration set), i.e. audio data representative of the case audio files, is needed to train a mapping between scores and likelihood ratios specific to the case. What audio can be deemed as representative of the case audio and what audio conditions to use as selection criteria is a subjective, case-specific decision by the forensic practitioner. This decision can be informed by research into the effect of audio conditions on the score-to-likelihood-ratio mappings and the resulting likelihood ratios. Using forensically relevant data, this type of research is done in this work. Multiple conditions are investigated in this manner, along with an analysis of the influence of number of speakers in the LR calculation set to serve as a baseline for variability. The results suggest duration differences below 40 s should be accounted for. Ethnolect differences, whether recordings are made in a car and speech durations above about 40 s appear not impactful. The same result is found for gender and the difference between operational data / lab data, except when cross-comparing those conditions.
Pediatric homicide represents one of the most severe forms of violence against children and remains an underexplored issue in Europe. The aim of the present study was to analyze the epidemiological, criminological, and autopsy-related characteristics of pediatric homicides and to identify potential age-related differences, which are essential to guide prevention and judicial investigation. A retrospective study was conducted on all autopsies of homicide victims under 18 years performed at the Institute of Forensic Medicine of Freiburg (Germany) between January 2000 and April 2025. Demographic, circumstantial, and post-mortem data were analyzed. Comparative analyses were performed between victims aged ≤ 1 year and > 1 year using Fisher's Exact test. A total of 39 cases were pediatric homicides. The victims' mean age was 4.3 years; 61.5% were male. Homicides were mainly intrafamilial (82.1%), and mothers were the predominant perpetrators among neonaticides. Asphyxia prevailed in victims ≤ 1 year (50.0% vs. 5.3%), whereas sharp force trauma predominated in older children (47.4% vs. 0%). All victims ≤ 1 year were killed indoors, while 36.8% of older victims were killed outdoors. Concealment of the body was significantly more frequent in victims ≤ 1 year (45.0% vs. 10.5%). The motives differed by age group, with concealed pregnancy and psychosocial crises predominating in neonaticides, and interpersonal conflict or sexual assault emerging in older victims. Pediatric homicides in the Freiburg district reveal two distinct profiles: early-life intrafamilial homicides driven by maternal crisis and concealment, and later childhood or adolescent cases characterized by overt violence and complex social dynamics. These findings underscore the importance of age-specific forensic approaches and multidisciplinary prevention strategies.
This study originates from a road traffic accident in which two vehicles collided in a curve. Alongside the physical evidence, location-related traces recovered from the Cache.sqlite database of an iPhone belonging to one of the drivers constituted the principal source of digital evidence. Beyond this specific case, analysis of these traces raised key forensic questions regarding their contribution to accident reconstruction. Based on these considerations, four investigative questions were defined, concerning the timing of the crash, phone manipulation before impact, speed estimation, and crash location. These questions were examined through a controlled experimental design involving 16 iPhone devices and high-precision Global Navigation Satellite System (GNSS) reference data, complemented by real casework observations. The results indicate that the moment of the crash can be approximated through speed analysis or spatial mapping of the recorded traces. Course values reflect the direction of motion rather than device orientation, thereby precluding their use for detecting phone handling. Speed values are reliable under steady-state conditions, but degrade substantially during braking. Regarding location, the analysis reveals three potential post-processing phenomena referred to as projection, correction, and anticipation. They can introduce significant positional errors, particularly around the moment of impact. These findings underline both the value and the limitations of iPhone location-related traces for forensic purposes. They further emphasise the need for a deeper understanding of their underlying creation mechanisms to ensure reliable interpretation in accident reconstruction.
Liquid chromatography tandem mass spectrometry (LC-MS/MS) methods are routinely used in forensic toxicology to confirm illicit drugs in oral fluid (OF). However, they are inherently limited to predefined analytes and may fail to detect newly emerging psychoactive substances (NPS) or compounds not included in routine panels. This study evaluates the applicability of a liquid chromatography-high resolution mass spectrometry (LC-HRMS) suspect screening workflow for the reanalysis of oral fluid extracts previously processed using a routine targeted LC-MS/MS method, with focus on its implementation in forensic casework. OF samples (0.25 mL) were extracted using a solid-phase extraction procedure routinely employed for the confirmation of traditional illicit drugs and psychopharmaceuticals. The same extracts were reanalyzed by LC-HRMS operating in data-dependent acquisition mode. Data processing was performed using a Personal Compound Database Library (PCDL) containing 2376 entries (1693 with MS/MS spectra), generated from HighResNPS and expanded with in-house acquired spectra and retention times. Qualitative validation was performed for 105 available reference standards, with limits of detection ≤ 10 ng/mL for 64.8% of them. The applicability of the workflow was demonstrated through the analysis of 25 authentic OF samples from drivers (n = 15), chemsex users (n = 6) and emergency unit patients (n = 4). LC-HRMS screening confirmed compounds previously detected by targeted LC-MS/MS, while enabling the identification of additional psychoactive substances not included in routine panels. This strategy provides a complementary approach for forensic toxicology laboratories, expanding screening capabilities from existing sample extracts and supporting the improved monitoring of emerging NPS in routine forensic casework.
INTRODUCTION:This study evaluated the prevalence of alcohol and the blood alcohol concentrations (BAC) among injured motor vehicle crash (MVC) patients admitted to a trauma center in Miami-Dade County, Florida. Results were compared with the BACs of driving under the influence (DUI) investigations in Miami-Dade County to determine whether there were significant differences in BAC among injured drivers and DUI investigations. METHOD:Patients included in the 7-month study had a blood sample provided for testing. Forensic blood specimens from DUI investigations in Miami-Dade County with incident dates in the patient specimen collection period were reviewed. Trauma specimens were analyzed for ethanol utilizing a gas chromatograph-flame ionization detector. DUI blood specimens were analyzed for ethanol using the same or comparable methods. RESULTS:Ethanol was detected in 23.8% of trauma patient drivers, with 19.6% having a BAC > 0.08 g/dL. Trauma patient BACs ranged from 0.023-0.388 g/dL (mean: 0.165 ± 0.073 g/dL). Among DUI investigations, 77.5% of subjects had ethanol detected, all with BAC > 0.08 g/dL, ranging from 0.125-0.358 g/dL (mean: 0.206 ± 0.062 g/dL). A significant main effect of driver type (p < 0.05) and significant interactions between type and sex and between type and age were observed. CONCLUSION:Alcohol was frequently detected among seriously injured drivers of an MVC, with most exceeding the legal limit. Although DUI investigation subjects exhibited significantly higher mean BACs, trauma patients also demonstrated concentrations consistent with impairment. Differences between groups may reflect enforcement practices rather than a reduced prevalence of alcohol-impaired driving.
The rapid emergence of novel synthetic opioids, including fentanyl analogues and nitazene-class substances, represents a critical public health concern. Their high potency and continuous structural modification demand highly sensitive and adaptable analytical approaches for reliable forensic detection. This study evaluates dried blood spot (DBS) sampling as a robust alternative to conventional liquid matrices for the identification of synthetic opioids. A method based on liquid chromatography coupled with high-resolution mass spectrometry (LC-HRMS) was developed and validated. Data acquisition was performed in full-scan data-dependent acquisition (DDA) mode. The combined DBS-LC-HRMS methodology is suitable for the detection of known fentanyl analogues and nitazenes, while also allowing the identification of potentially unknown compounds through data analysis. The limits of detection (LOD) and quantification (LOQ) ranged from 0.05 to 0.2 ng/mL and 0.1-0.75 ng/mL, respectively. The method established a linear range of 0.5-3 ng/mL for all analytes, with validation results supporting the suitability of DBS as a sample storage and pre-treatment approach, with simplified collection, storage and transport compared to traditional matrices. Stability was also assessed, demonstrating that DBS is a more robust and cost-effective approach for analyte preservation than frozen whole blood over a 7 days period. Furthermore, the method was successfully applied to real samples, confirming its suitability as an effective tool for forensic toxicology screening and analysis. The proposed workflow demonstrated satisfactory analytical performance, enabling the identification and quantification of 37 synthetic opioids; Overall, this strategy provides a flexible and efficient tool for routine forensic toxicology, with the capacity to adapt to the dynamic and evolving landscape of illicit synthetic opioids.
