Evidence of mephedrone chronic abuse through hair analysis using GC/MS

Mephedrone is a synthetic derivative of cathinone which is becoming more common on the recreational drug market. Several intoxications following mephedrone abuse have been reported though published papers have focused essentially on analytical approaches for biological fluids and only one has involved a hair sample. After the development and validation of a new method, the first series of positive results for mephedrone in hair specimens is reported here. After decontamination of the hair strand in methylene chloride, hair segments were cut into small pieces with scissors, weighed and incubated overnight in Soerensen buffer pH 7.0 in the presence of deuterated 3,4-methylenedioxymethamphetamine (MDMA) at 40°C. The incubation medium was extracted using ethyl acetate after alkalinisation with 1N sodium hydroxide (NaOH). Before injection, the dry extract was derivatized using a mixture of heptafluorobutyric anhydride/ethyl acetate (100:50, v/v), evaporated and dissolved in ethyl acetate (25μl). After introduction of 1μl of the extract onto a splitless injector, chromatographic separation was achieved on a HP 6890 gas chromatograph equipped with a 5-MS capillary column. Detection was achieved in single ion monitoring mode (m/z 254-119-210 for mephedrone, m/z 258-213 for MDMA-d5) using a 5973 MSD operating in electron impact mode. Sixty-seven hair specimens were tested for mephedrone. Thirteen of them were found positive for mephedrone with concentrations ranging from 0.2 to 313.2ng/mg with a mean concentration of 26.8ng/mg. It was difficult to compare our findings due to a lack of reference data, nevertheless mephedrone seems well incorporated into hair (concentrations in the ng/mg range) like other stimulant drugs such as amphetamines or cocaine. The aim of this work was to develop a specific and accurate method for mephedrone analysis in hair specimens and its application to a large number of samples (n=67). The developed analytical method appears sensitive enough to reveal occasional to regular use of mephedrone.     

Experimental study of the expansion dynamic of 9 mm Parabellum hollow point projectiles in ballistic gelatin

We study in this paper the expanding behaviour of hollow point 9 mm Parabellum projectiles (Hornady XTP(?) and Speer Gold Dot(?)). We defined a deformation rate that takes into account both the diameter increase and the length reduction. We plotted the behaviour of this parameter versus impact velocity (we refer to this curve as the expanding law). This expanding law has been plotted for different gelatin weight ratios and different gelatin block lengths. We completed our experiments with a set of high speed movies in order to correlate the deceleration to the state of expansion and size of the temporary cavity. Our results pointed out that full expansion is reached shortly after the projectile fully penetrates the gelatin. This result shows that the key point to accurately simulate human body interaction with a hollow point projectile is to accurately simulate the interface (skin, skull, clothes thoracic walls). Simulating accurately organs is only an issue if a quantitative comparison between penetration depths is required, but not if we only focus on the state of expansion of the projectile. By varying the gelatin parameters, we discovered that the expanding law exhibits a velocity threshold below which no expansion occurs, followed by a rather linear curve. The parameters of that expanding law (velocity threshold and line slope) vary with the gelatin parameters, but our quantitative results demonstrate that these parameters are not extremely critical. Finally, our experiments demonstrate that the knowledge of the expansion law can be a useful tool to investigate a gunshot in a human body with a semi-jacketed projectile, giving an estimation of the impact velocity and thus the shooting distance.     

The use of the likelihood ratio for evaluative and investigative purposes in comparative forensic handwriting examination

This paper extends previous research and discussion on the use of multivariate continuous data, which are about to become more prevalent in forensic science. As an illustrative example, attention is drawn here on the area of comparative handwriting examinations. Multivariate continuous data can be obtained in this field by analysing the contour shape of loop characters through Fourier analysis. This methodology, based on existing research in this area, allows one describe in detail the morphology of character contours throughout a set of variables. This paper uses data collected from female and male writers to conduct a comparative analysis of likelihood ratio based evidence assessment procedures in both, evaluative and investigative proceedings. While the use of likelihood ratios in the former situation is now rather well established (typically, in order to discriminate between propositions of authorship of a given individual versus another, unknown individual), focus on the investigative setting still remains rather beyond considerations in practice. This paper seeks to highlight that investigative settings, too, can represent an area of application for which the likelihood ratio can offer a logical support. As an example, the inference of gender of the writer of an incriminated handwritten text is forwarded, analysed and discussed in this paper. The more general viewpoint according to which likelihood ratio analyses can be helpful for investigative proceedings is supported here through various simulations. These offer a characterisation of the robustness of the proposed likelihood ratio methodology.     

Raman spectroscopy and microspectrophotometry of reactive dyes on cotton fibres: Analysis and detection limits

A collaborative study on Raman spectroscopy and microspectrophotometry (MSP) was carried out by members of the ENFSI (European Network of Forensic Science Institutes) European Fibres Group (EFG) on different dyed cotton fabrics. The detection limits of the two methods were tested on two cotton sets with a dye concentration ranging from 0.5 to 0.005% (w/w). This survey shows that it is possible to detect the presence of dye in fibres with concentrations below that detectable by the traditional methods of light microscopy and microspectrophotometry (MSP). The MSP detection limit for the dyes used in this study was found to be a concentration of 0.5% (w/w). At this concentration, the fibres appear colourless with light microscopy. Raman spectroscopy clearly shows a higher potential to detect concentrations of dyes as low as 0.05% for the yellow dye RY145 and 0.005% for the blue dye RB221. This detection limit was found to depend both on the chemical composition of the dye itself and on the analytical conditions, particularly the laser wavelength. Furthermore, analysis of binary mixtures of dyes showed that while the minor dye was detected at 1.5% (w/w) (30% of the total dye concentration) using microspectrophotometry, it was detected at a level as low as 0.05% (w/w) (10% of the total dye concentration) using Raman spectroscopy. This work also highlights the importance of a flexible Raman instrument equipped with several lasers at different wavelengths for the analysis of dyed fibres. The operator and the set up of the analytical conditions are also of prime importance in order to obtain high quality spectra. Changing the laser wavelength is important to detect different dyes in a mixture.     

Synthetic cannabinoids in "spice-like" herbal blends: First appearance of JWH-307 and recurrence of JWH-018 on the German market

Herbal smoking blends, available on the German market were analyzed and several known synthetic cannabinoids were identified (JWH-122 and JWH-018). In addition, we isolated a new active ingredient by silica gel column chromatography and elucidated the structure by nuclear magnetic resonance (NMR) methods. The compound was identified as JWH-307, a synthetic cannabinoid of the phenyl-pyrrole subclass with known in vitro binding affinities for cannabinoid receptors. To date, this is the first appearance of this subclass of cannabimimetics in such products. JWH-307 has been further characterized by gas chromatography accurate mass spectrometry (GC-HRMS), electrospray tandem mass spectrometry (ESI-MS/MS), ultraviolet (UV) and infrared (IR) spectroscopy. JWH-018 was among the first compounds banned by many countries world-wide including Germany. The identification of JWH-018 was striking, since this is the first report where JWH-018 recurred on the German market thus violating existing laws. A generic method was established to quantify synthetic cannabinoids in herbal smoking blends. Quantification was achieved using an isotopically labeled standard (JWH-018-D(3)). JWH-018 was found at a level of 150mg/g while JWH-122 and JWH-307 occurred as a mixture at a total level of 232mg/g.     

THCVA-A - a new additional marker for illegal cannabis consumption

The aim of the present investigations was to find markers for differentiating between the consumption of illegal cannabis products and legal medication containing fully synthetic Δ9-tetrahydrocannabinol (Δ9-THC), e.g., Marinol capsules. Δ9-Tetrahydrocannabinolic acid A (Δ9-THCA-A) and Δ9-tetrahydrocannabivarinic acid A (Δ9-THCVA-A) were taken into consideration for analysis, because these substances are the precursors of Δ9-THC and Δ9-tetrahydrocannabivarin (Δ9-THCV) in plant material of Cannabis sativa and are not contained in medical THC formulations. Whereas Δ9-THCA-A is an already well investigated substance, there is little analytical data on Δ9-THCVA-A. The reason for the presented investigations was a case in which a man was tested positive for Δ9-THC during a routine traffic control claiming that the positive serum sample resulted from the intake of a THC medication (Marinol) and not from consuming illegal cannabis products. Sample preparation consisted of a protein precipitation with acetonitrile. Analysis was carried out on a Thermo Fisher LCQ Deca ion trap LC-MS-MS-system using electron spray ionization (ESI) in negative mode. MS(2)- and MS(3)-full scan spectra were recorded for Δ9-THCA-A and Δ9-THCVA-A starting from [M-H](-). Reference spectra were obtained by measuring a Δ9-THCA-A reference solution and an ethanolic cannabis extract for Δ9-THCVA-A as there is no reference material for this cannabinoid available on the market yet. Main transitions for Δ9-THCA-A were m/z 357→313 and 339 in the MS(2)-spectrum and m/z 313→245 and 191 in the MS(3)-spectrum. Fragmentation pattern of Δ9-THCVA-A was identical with a difference of 28 amu less for the precursor ion as well as the fragments due to a shorter alkyl side chain in the molecule (MS(2): m/z 329→285 and 311; MS(3): m/z 285→217 and 163). The two plant cannabinoids Δ9-THCA-A and Δ9-THCVA-A could be detected in the serum sample by LC-MS-MS which proved the intake of illegal cannabis products derived from plant material of C. sativa in the described case.     

Victims' influence on intimate partner violence revictimization: an empirical test of dynamic victim-related risk factors

Research has reported that not only characteristics of the perpetrator but also characteristics of the victim influence risk for intimate partner violence (IPV). This would suggest that prevention of repeat abuse could benefit from a focus on both perpetrator and victim characteristics. Knowledge on factors that are within victims' sphere of influence is important because a focus on victim characteristics can help victims to take control of their situations and can thereby empower them. Dynamic victim-related factors are most relevant here as these are factors that can be changed or improved, in contrast to unchangeable static factors. Surprisingly, however, little is known about how victim-related factors affect risk for revictimization of IPV. The current study was conducted among a Dutch sample of 156 female, help-seeking IPV victims. The aim was to examine to what extent prior IPV and, in particular, dynamic victim-related factors influence risk for future IPV. In accordance with the models articulated by Foa, Cascardi, Zoellner and Feeny, we studied how the three key factors from their models-partner violence, victims' psychological difficulties, and victims' resilience-related to risk for IPV revictimization. Results provide support for several key factors (partner violence and victims' psychological difficulties) and, moreover, show which victim-related factors contribute to revictimization risk above and beyond the influence of prior violence committed by a partner against the victim (i.e., victims' prior IPV victimizations). Findings are discussed in terms of recommendations for practice and future research.     

Determining the Refractive Index Variation within Panes of Vehicle Windshield Glass

Refractive indices of seven double‐paned vehicle windshields were measured to assess the variation across the pane of glass and to evaluate collection techniques for known glass standards by comparing false negative rates. Measurements were made using a Foster and Freeman GRIM3 instrument, and a minimum of 240 measurements were made per pane. The mean SD of the windshields was 0.00004. It was further determined that collecting a known sample from two different sections of a shattered windshield gave the lowest rate of false negatives when using ± 2 standard deviations to estimate the RI variation of the known glass. Additionally, refractive indices often were highest in the center of the windshield and decreased toward the left and right edges; in approximately half the sample set, the two panes of a single windshield were differentiated by one or more properties.