The impact of fentanyl on DUIDs and traffic fatalities: Blood and oral fluid data

Fentanyl has emerged as the most prolific drug in the ongoing opioid epidemic and has greatly impacted traffic safety in recent years. This study aimed to evaluate fentanyl prevalence and concentrations in blood and oral fluid in driving under the influence of drugs (DUID) cases in three different regions (i.e., Alabama, Orange County, CA, and Houston, TX) from 2017 to 2022. Furthermore, traffic fatalities were evaluated for Alabama and Orange County, CA. Fentanyl positivity in DUID and traffic fatalities increased for most years in this study. In Alabama, the prevalence of fentanyl DUID cases increased 4-fold in 2022 compared to 2017. Orange County's increase from 2017 to 2022 was 14-fold. In Houston, the increase was approximately 2-fold from 2019 to 2022. The greatest increase for all laboratories coincided with the start of the COVID-19 pandemic. In 2022, the median fentanyl DUID blood concentrations were 4.7, 11, and 4.7 ng/mL in Alabama, Orange County, and Houston, respectively. Most fentanyl cases were polydrug cases (≥90%). Methamphetamine, THC, and alprazolam were the most frequently detected drugs in combination with fentanyl. Alabama has collected oral fluid and blood in DUID cases since 2018. The detection of fentanyl in oral fluid was comparable to blood. However, 59% and 8.7% of fentanyl-positive cases had concentrations of >20 ng/mL in oral fluid and blood, respectively. Therefore, oral fluid as an alternative or supplemental specimen to blood is an attractive approach for fentanyl in DUID cases. This study contributes to understanding recent fentanyl trends and their impact on traffic safety.     

Forensic integrity verification of video recordings based on MTS files

Digital video is used in criminal trials as evidence with legal responsibility because video content vividly depicts events occurring at a crime scene. However, using sophisticated video editing software, assailants can easily manipulate visible clues for their own benefit. Therefore, the integrity of digital video files acquired or submitted as evidence must be ensured. Forensic analysis of digital video is key to ensuring the integrity of links with individual cameras. In this study, we analyzed whether it is possible to ensure the integrity of MTS video files. Herein, we propose a method to verify the integrity of MTS files encoded by advanced video coding high definition (AVCHD), which is frequently used for video recording. To verify MTS file integrity, we propose five features. Codec information, picture timing, and camera manufacture/model are modified AVI and MP4-like format video verification features. Group of pictures and Universally Unique Identifier patterns were specifically developed for MTS streams. We analyzed the features of 44 standard files recorded using all recording options of seven cameras. We checked whether integrity can be validated on unmanipulated videos recorded in various environments. In addition, we considered whether manipulated MTS files edited in video editing software could be validated. Experimental results show that all unmanipulated and manipulated MTS files with known recording devices were discriminated only when all five features were checked. These results show that the proposed method verifies the integrity of MTS files, strengthening the validity of MTS file-based evidence in trials.     

Compounds identified in an illicit generic Xanax tablet are the result of a failed synthesis of alprazolam

Unintended compounds produced by inexperienced clandestine chemists may present a challenge in laboratories tasked with their identification. In March 2020, an anonymously submitted tablet purchased as a generic form of Xanax was analyzed by Erowid's DrugsData.org . The gas chromatography–mass spectrometry (GC–MS) results publicly released online indicated several unidentified compounds due to a lack of database references at that time. Elucidation by our group indicated the presence of several structurally related compounds that were linked to a failed synthesis of alprazolam. For this case study, a published procedure for the synthesis of alprazolam starting with the chloroacetylation of 2-amino-5-chlorobenzophenone was identified as a potential source of this failure. The procedure was reproduced to identify pitfalls of the methodology and examine its possible link to the illicit tablet. Reaction outcomes were analyzed via GC–MS and compared to the tablet submission data. The major compound in this submission, N-(2-benzoyl-4-chlorophenyl)-2-chloroacetamide, along with several related byproducts were successfully reproduced indicating that the tablet contents potentially stem from a failure to synthesize alprazolam.     

Automated detection of regions of interest in cartridge case images using deep learning

This paper explores a deep-learning approach to evaluate the position of circular delimiters in cartridge case images. These delimiters define two regions of interest (ROI), corresponding to the breech face and the firing pin impressions, and are placed manually or by an image-processing algorithm. This positioning bears a significant impact on the performance of the image-matching algorithms for firearm identification, and an automated evaluation method would be beneficial to any computerized system. Our contribution consists in optimizing and training U-Net segmentation models from digital images of cartridge cases, intending to locate ROIs automatically. For the experiments, we used high-resolution 2D images from 1195 samples of cartridge cases fired by different 9MM firearms. Our results show that the segmentation models, trained on augmented data sets, exhibit a performance of 95.6% IoU (Intersection over Union) and 99.3% DC (Dice Coefficient) with a loss of 0.014 for the breech face images; and a performance of 95.9% IoU and 99.5% DC with a loss of 0.011 for the firing pin images. We observed that the natural shapes of predicted circles reduce the performance of segmentation models compared with perfect circles on ground truth masks suggesting that our method provide a more accurate segmentation of the real ROI shape. In practice, we believe that these results could be useful for firearms identification. In future work, the predictions may be used to evaluate the quality of delimiters on specimens in a database, or they could determine the region of interest on a cartridge case image.     

Development of etching paste for serial number restoration on aluminum engine block

Engine numbers, which involve information regarding the engine type, production number, and year and place of manufacture, are used for identification purposes. Comprising of unique alphanumeric characters, the engine numbers are fully or partially obliterated especially in auto theft and smuggling cases to conceal the origin, identity, and owner of vehicles. The limitations of the current restoration techniques such as the difficulty of using chemical liquid etching in vertical sites, the restrictions of magnetic and optical methods, and the applicability of several techniques like electron backscatter diffraction only in the laboratory environment prompt the development of new techniques. In view of these limitations and the importance of restoring engine numbers in criminal investigations, this unique study aimed to develop an etching paste that would restore the effaced characters on a real aluminum alloy engine block. The characters which were cold-stamped on the engine block were milled at varying depths and restoration attempts were conducted using etching pastes formed with different chemicals and materials. The analyses indicate that the etching paste formed with 200 mg of perlite, 400 mg of iron powder, and 450 μL of 20 M NaOH provided restoration to a good extent. The prevention of over-etching through the controlling of the chemical reaction and the cost-effectiveness appears to be the advantages of this technique. The success of recovery on the real engine block, the facilitation of restoration on curved surfaces, and the chance of on-site usage will likely make the etching paste a widely used tool in serial number restoration.     

Piercing the surface: A mechanical analysis of stabbing with household tools

Estimating the applied power during a stabbing incident, or estimating the minimal force necessary to penetrate the body with a certain weapon is a challenging task in forensic practice. A thorough forensic evaluation of stabbing forces needs objective numerical experimental data. Stabbing tests of 12 different weapons – including knives, a pair of scissors, a fork, screwdrivers, a rasp, a corkscrew, and a utility knife blade – were performed with a Mecmesin MultiTest-dV material tester on pork loin and ballistic gel to estimate the stabbing forces and dynamics. Penetration force (F_p) and maximal force (F_max) were recorded, and the registered force curves were analyzed. F_max was 159.8–212.07 Newton (N), 30.56–30.58 N, 168.9–185.48 N for various knives; 171.39–190.43 N for the pair of scissors, 233.6 N for the fork; 532.65–562.65 N, 370.31–367.19 N and 314.51–432.89 N for various screwdrivers, 44.14–56.62 N for utility knife during pork loin stabbing. The butter knife, corkscrew and rasp were not able to penetrate the pork loin, and the curved fork bent during stabbing. The results prove that weapon characteristics greatly influence the force necessary for penetration. Maximal stabbing force depends mostly on tip sharpness, and the force sharply decreases after penetration occurs, which indicates that edge sharpness is not as important as tip characteristics during stabbing perpendicular to skin surface. The penetration force during stabbing with a pair of scissors is comparable to the penetration force of knives. Stabbing with screwdrivers generally needs larger force than average knives but depends greatly on screwdriver size.     

Organic impurity profiling of fentanyl samples associated with recent clandestine laboratory methods

Nearly a decade ago, fentanyl reappeared in the United States illicit drug market. In the years since, overdose deaths have continued to rise as well as the amount of fentanyl seized by law enforcement agencies. Research surrounding fentanyl production has been beneficial to regulatory actions and understanding illicit fentanyl production. In 2017, the Drug Enforcement Administration (DEA) began collecting seized fentanyl samples from throughout the United States to track purity, adulteration trends, and synthetic impurity profiles for intelligence purposes. The appearance of a specific organic impurity, phenethyl-4-anilino-N-phenethylpiperidine (phenethyl-4-ANPP) indicates a shift in fentanyl production from the traditional Siegfried and Janssen routes to the Gupta-patent route. Through a collaboration between the DEA and the US Army's Combat Capabilities Development Command Chemical Biological Center (DEVCOM CBC), the synthesis of fentanyl was investigated via six synthetic routes, and the impurity profiles were compared to those of seized samples. The synthetic impurity phenethyl-4-ANPP was reliably observed in the Gupta-patent route published in 2013, and its structure was confirmed through isolation and structure elucidation. Organic impurity profiling results for illicit fentanyl samples seized in late 2021 have indicated yet another change in processing with the appearance of the impurity ethyl-4-anilino-N-phenethylpiperidine (ethyl-4-ANPP). Through altering reagents traditionally used in the Gupta-patent route, the formation of this impurity was determined to occur through a modification of the route as originally described in the Gupta patent.     

Fatal intoxication involving 2-methyl AP-237

Novel synthetic opioids contribute considerably to the opioid epidemic, especially with the frequent emergence of structurally similar compounds. This case report describes a fatal intoxication involving 2-methyl AP-237. A 54-year-old Caucasian male was found deceased from an apparent drug overdose. A plastic container labeled “2MAP” and a cut straw were found in the decedent's backpack at the scene. A white substance found in the container tested positive for fentanyl by field testing. According to his medical history, the decedent was treated for a drug overdose 3 years prior to his death. With no diagnostic findings at autopsy, the case was submitted for toxicological analysis. An unknown substance was detected in peripheral blood and urine using gas chromatography with nitrogen phosphorous detection (GC-NPD). Further testing was conducted using gas chromatography–mass spectrometry (GC–MS) and liquid chromatography-quadrupole-time-of-flight mass spectrometry (LC-QTOF-MS) which confirmed the presence of 2-methyl AP-237 and potential metabolites in blood and urine. Quantitation by GC-NPD revealed concentrations of 2-methyl AP-237 in blood and urine at 480 ng/mL and 4200 ng/mL, respectively. The toxicological analysis also identified and quantitated alprazolam in the blood at 55 ng/mL. Additionally, the metabolism of 2-methyl AP-237 was investigated and three hydroxylated metabolites were identified in peripheral blood and urine. Limited literature is available for the detection and quantitation of 2-methyl AP-237 in postmortem specimens. Given the toxicological findings with unremarkable autopsy findings, this case is an example of a fatal intoxication involving 2-methyl AP-237.     

2,4,6-Tri(2′-pyridyl)-1,3,5-triazine for determination of iron(II), Iron(III), and total iron contents on human palms

When iron-based tools, such as knives or guns, are held, traces of iron can transfer to the skin. However, no previous studies have been published regarding the effect of the elapsed contact time on the transfer of iron species with different valences to the palm. Compared with 3-(2-pyridyl)-5,6-diphenyl-1,2,4-triazine (PDT), 2,4,6-tri(2′-pyridyl)-1,3,5-triazine (TPTZ) was found to exhibit a higher sensitivity to iron(II) spectrophotometrically. This work employed 2,4,6-tri(2′-pyridyl)-1,3,5-triazine (TPTZ) and UV spectrophotometry to determine the amounts of iron(II), iron(III), and total iron transferred to human palms from iron tools. It was found that the palmar moisture level was an important factor in determining the amounts of total iron, including iron(II), transferred to the palm. For identical contact times, the amounts of total iron transferred to the palm was proportional to the palmar moisture, and the difference between the maximum and minimum amounts was 12 μg per hand. However, the amounts of iron(II) transferred to the palm gradually decreased over time for low palmar moisture levels, but steadily increased over time for high palmar moisture levels. Additionally, for average levels of palm moisture, the amounts of iron(II) and iron(III) transferred to the palm gradually decreased and increased, respectively, with longer contact times. Notably, this research could serve as a theoretical basis and guide for the detection of trace iron species with different valences on human palms for criminal investigations.     

Ballistic impact of hollow-point ammunition on porcine bone

Identifying failure mechanisms in skeletal tissue allows a deeper understanding of the effects of specific projectile impacts on bone. While ballistic trauma in flat bones is largely researched, knowledge of how long bones react to gunshot impacts is limited in the literature. The impacts of deforming ammunition appear to produce higher levels of fragmentation; however, these have not been studied in depth. This study compares the damage to femora bone by HP 0.357 and 9 mm projectiles constructed with both full and semi-metal jackets. Impact experiments were undertaken on a single-stage light gas gun involving the use of a high-speed video camera and full reconstruction of the bones to ascertain fracture patterns occurring in the femora. Higher degrees of fragmentation are likened to the presence of semi-jacketed HP projectiles than jacketed HP projectiles. The observations of external facing beveled edges are believed to be associated with the increased separation of the jacket and lead core of projectiles. Additionally, experimentation has shown that the amount of kinetic energy lost postimpact is likely related to the presence or the absence of a metal jacket on an HP projectile. The observed data, therefore, suggest that the composition, rather than the configuration, of a projectile affects the type and extent of the damage.