Evaluation of gunshot residue (GSR) evidence: Surveys of prevalence of GSR on clothing and frequency of residue types.

The evaluative approach is a logical approach to interpreting scientific findings in criminal cases, applying knowledge regarding the transfer, persistence and recovery of particulate material. The application of this approach to interpreting the finding of gunshot residue on the clothing of a suspect requires knowledge of background levels of GSR on clothing and on the frequency of different residue types in a particular environment. The cuffs of 100 upper outer garments submitted to a forensic laboratory in connection with non-firearms offences were sampled for gunshot residue. No 3-component lead/antimony/barium particles were found on 98 of them. Two 3-component particles were found on one of them and one 3-component particle was found on another. The frequency of occurrence of various particle types regarded as consistent with GSR was also explored. The findings show that, while 3-component particles were somewhat more likely to be encountered by chance on clothing than on hands, they are still relatively uncommon events. To investigate the frequency of occurrence of particular residue types, 100 discharged rounds of ammunition recovered at crime scenes were sampled and the types of residue present were determined. The results show that some residue types are significantly more common than others. Both sets of data will be of value in evaluating the significance of finding GSR on clothing of suspects in criminal cases.

Identification of (2-aminopropyl)indole positional isomers in forensic samples.

In 2012, 5-(2-aminopropyl)indole (5-API, 5-IT) was reported by Norwegian authorities to the European Monitoring Centre for Drugs and Drug Addiction (EMCDDA) via the Early Warning System (EWS). The 3- isomer, 3-(2-aminopropyl)indole (3-API, AMT, alpha-methyltryptamine), has been available on the recreational drugs market for a somewhat longer time, having first been reported to the EMCDDA by Finnish authorities in 2001. Both isomers are available from online vendors of 'legal highs'. Recently, three forensic drug cases (two tablets and one powder) were presented for routine analysis and the active constituent was tentatively identified as an API isomer. The six positional isomers (2-, 3-, 4-, 5-, 6- and 7-(2-aminopropyl)indoles) were synthesized and analyses by a combination gas chromatography-mass spectrometry (GC-MS), and liquid chromatography-mass spectrometry (LC-MS) showed that these could be readily discriminated thus facilitating the identification of 3-API in the tablets and 5-API in the powder. With exception of 5- and 6-APIs, which co-eluted, it was found possible to separate the isomers by GC without derivatization. LC separation also proved to be a feasible method for the discrimination of the isomers. Although the 2- and 7- isomers were not fully resolved by LC, it was found possible to distinguish them using their product ion spectra as the 2- isomer produced the m/z 132 fragment ion formed by loss of vinylamine, whereas the 7- isomer formed m/z 158 through loss of methylamine. In the synthesis 2-API, a novel tricyclic by-product was formed in an annulation reaction where the reaction solvent, tetrahydrofuran, was incorporated into the molecule.

The identification of 4-methylamphetamine and its synthesis by-products in forensic samples.

During the analysis of street samples for the suspected presence of controlled drugs, two samples were found to contain 4-methylamphetamine (4-MA). This is the first report of the drug in Ireland as previously only N-methylamphetamine (N-MA) had been encountered. In Ireland, little attention had previously been paid to the possible presence of the isomeric forms of methylamphetamine in submitted samples. Two street level samples were analyzed and the presence of 4-MA was confirmed in both, the other major components of these samples were examined to establish the possible synthetic route employed. The identification of a single synthetic route which accounted for the major components found in the street samples has implications for previously thought route specific analogous compounds of 4-MA. The three ring substituted isomers of methylamphetamine, namely 2-, 3- and 4-MA, were synthesized and characterized by GCMS, HR-ESIMS, NMR and IR for use as reference standards.

'Smoking' mephedrone: the identification of the pyrolysis products of 4-methylmethcathinone hydrochloride.

The ring-substituted cathinone - mephedrone - has gained popularity among recreational drug users over the past several years. It is generally consumed orally or by snorting but reports indicate that it is also ingested by vaporization/inhalation. This study examines the pyrolysis products produced by heating mephedrone under using simulated 'meth pipe' conditions. Thirteen pyrolysis products were identified, the major ones being iso-mephedrone, 4-methylpropiophenone, 4-methylphenylacetone, two pyrazine derivatives formed by dimerization of mephedrone, N-methylated mephedrone (N,N,4-trimethylcatinone), two hydroxylated oxidation products and a diketone. Other minor products formed were identified as 4-methylacetophenone, two α-chloro ketones and N-methylated iso-mephedrone.

The synthesis and characterization N-methyl-3-phenyl-norbornan-2-amine (Camfetamine™).

N-Methyl-3-phenyl-norbornan-2-amine (N-methyl-3-phenylbicyclo[2.2.1]heptan-2-amine, Camfetamine(™) ) is available from a number of online legal highs/research chemicals' vendors. Although it was developed as an analeptic by Merck in the early 1960s, it was never commercialized. However, the Association of Independent Research Chemical Retailers (AIRCR), an umbrella organization for a number of online vendors, has redeveloped it for use as a recreational drug. N-Methyl-3-phenyl-norbornan-2-amine is closely related to fencamfamine which has been widely used as a central nervous system (CNS) stimulant and appetite suppressant. In this paper we describe the synthesis of N-methyl-3-phenyl-norbornan-2-amine, its characterization and interpretations of its electron impact, and electrospray ionization mass spectra.

The analysis of amphetamine-like cathinone derivatives using positive electrospray ionization with in-source collision-induced dissociation.

RATIONALE: Amphetamine-like cathinone derivatives have become popular as recreational drugs over the past several years but their identification for forensic purposes is made difficult as they undergo extensive fragmentation under commonly used electron ionization (EI) conditions to afford ambiguous mass spectra. To overcome this, the feasibility of using positive electrospray ionization (ESI) with in-source collision-induced dissociation (CID) to produce distinguishable product ion mass spectra was examined. METHODS: A set of six homologous cathinone derivatives was analyzed using an LTQ/Orbitrap™ high-resolution mass spectrometer to establish if there are any commonalities or uniqueness in their mass spectra. These compounds and a number of other cathinone derivatives were also analyzed on a single quadrupole mass spectrometer to establish the feasibility of using in-source CID for their identification in forensic drug samples. RESULTS: The ESI product ion mass spectra of the [M + H](+) ions of six model compounds were found to be readily interpretable and product ion formation pathways are presented. The use of such mass spectral data in the analysis of forensic drug samples facilitated the discrimination of closely related cathinone derivatives that were difficult to distinguish using conventional gas chromatography/electron ionization mass spectrometry. A product ion mass spectral library of 22 commonly encountered cathinone derivatives was also developed. CONCLUSIONS: It has been shown that the product ion ESI mass spectra of cathinone derivatives are readily interpretable and are useful for the identification of this drug group in forensic samples.

The analysis of substituted cathinones. Part 3. Synthesis and characterisation of 2,3-methylenedioxy substituted cathinones.

The first synthesis of the 2,3-isomers of MDPV, butylone and methylone is reported. The isomers were characterised by (1)H and (13)C NMR spectroscopy and compared to the corresponding 3,4-isomers. A GC method is described which separates the 3,4- and the 2,3-isomers from each other. IR spectra of the 2,3-isomers are also compared with the corresponding 3,4-isomers. Two seized drug samples were analysed by GCMS and the samples were found to contain the 3,4-isomers.

The transfer of touch DNA from hands to glass, fabric and wood.

The transfer of DNA from hands to objects by holding or touching has been examined in the past. The main purpose of this study was to examine the variation in the amount of DNA transferred from hands to glass, fabric and wood. The study involved 300 volunteers (100 for glass, 100 for fabric and 100 for wood) 50% of which were male and 50% female. The volunteers held the material for 60s. The DNA was recovered from the objects using a minitape lift, quantified using the Quantifiler kit assay, extracted using a 'Qiagen(®) QIAamp DNA mini kit' and amplified using the AmpFlSTR(®) SGM Plus™ Amplification Kit at 28 cycles. The results show that using ANOVA there was a significant difference (F=8.2, p<0.05) between the three object types in the amount of DNA recovered. In terms of DNA transfer and recovery, wood gave the best yield, followed by fabric and then glass. The likelihood of success of obtaining a profile indicative of the holder was approximately 9% for glass samples, 23% for fabric and 36% for wood. There was no significant difference between the amount of DNA transferred by male or female volunteers. In this study good shedder status, as defined by obtaining useful profiles of 6 or more alleles, is estimated at approximately 22% of the population. The phenomenon of secondary transfer was observed when mixed DNA profiles were obtained but the incidence was low at approximately 10% of the total number of samples. DNA profiles corresponding to more than one person were found on objects which had been touched by only one volunteer. Although secondary transfer is possible the profiles obtained from touched objects are more likely to be as a result of primary transfer rather than a secondary source.

The syntheses and characterization 3ß-(4-fluorobenzoyloxy)tropane (fluorotropacocaine) and its 3α isomer.

3ß-(4-Fluorobenzoyloxy)tropane (3ß-FBT, fluorotropacocaine) was first reported by Finnish authorities to the European Monitoring Centre for Drugs and Drug Addiction (EMCDDA) via the Early Warning System (EWS) in 2008 and our own laboratory tentatively identified it in 2010 in several products purchased from head shops. Very little is known about this cocaine-like drug and, as no reference standards were available, we have synthesized and characterized both 3ß-FBT and its 3α isomer for use as reference standards. The two compounds are separable by gas chromatography (GC) but their electron-impact (EI) mass spectra were found to be almost identical. ¹9F NMR spectroscopy was also found to be a useful technique for distinguishing the two isomers.

Homicide/suspicious death statistics for cases submitted to the forensic science laboratory in the Republic of Ireland for 2004-2008.

The purpose of this study was to examine the trends and patterns of homicide in the Republic of Ireland over a five-year period (2004-2008). In total, 293 cases are covered in the survey. The majority of the victims were men. The most common age group of victims was 20-29 years old. The majority of the suspects were also men. The most common age was also 20-29 years old. Stabbing was the most common method used to kill and this often featured multiple wounds to the head and body. Shooting and blunt force traumas were also common. Homicides are more likely to occur over the weekend period. This study also explored the relationship between the suspect and the victim, the motive and the location of the fatal assault. In the majority of cases, the victim and the perpetrator were known to each other. The site of the fatal assault was most likely to be a residence and the most frequent motive was an argument/quarrelling. A small number of cases involved multiple fatalities, often involving relatives. The figures were compared with other international studies; our findings are broadly in agreement with them.

The analysis of substituted cathinones. Part 2: an investigation into the phenylacetone based isomers of 4-methylmethcathinone and N-ethylcathinone.

During the analysis of "seized samples", suspected of containing 4-methylmethcathinone (mephedrone) and N-ethylcathinone (ethcathinone) additional compounds were observed in the GCMS chromatogram. These compounds were suspected to be the corresponding phenylacetone isomers of mephedrone and ethcathinone respectively. These isomers are referred to as iso-mephedrone and iso-ethcathinone, respectively. The identity of these compounds was verified by synthesising the isomers from known starting materials and comparing them with the compounds found in the seized samples. Analytical data, GCMS, NMR and IR on these compounds are provided. Possible explanations for the presence of these compounds in the seized samples are explored. Contaminated starting material is one suggestion. Rearrangement of the propiophenone based product to the phenylacetone based product is also suggested. The reaction of the α-bromopropiophenone with a primary amine can also lead to the phenylacetone based product. The presence of these isomeric compounds in seized samples could be used to compare different samples and attempt to establish a common origin.

The analysis of substituted cathinones. Part 1: chemical analysis of 2-, 3- and 4-methylmethcathinone.

The ring substituted methyl isomers of methcathinone, 2-, 3- and 4-methylmethcathinone were analysed. The 2- and 3-isomers were synthesized. The 4-methylmethcathinone isomer is also known as mephedrone and has been widely studied. We present GCMS, NMR and IR data for the three isomers. We show that the three isomers can be separated by GCMS and that the IR spectra for the three compounds can be used to distinguish between them. A seized sample was analysed and it was found to contain 4-methylmethcathinone and benzocaine.

The recovery and persistence of salivary DNA on human skin.

Salivary DNA is encountered in many crimes, such as sexual assaults and murders. In this study, saliva from three male donors was deposited on the skin of three female recipients. The amount of male salivary DNA remaining on the female skin was measured over a 96-h period using the Quantifiler™ Y Human Male DNA Quantification Kit. In eight of the nine experiments, a full male DNA profile matching the donor was obtained even after 96 h. In addition, the study showed that the concentration of salivary DNA varied from donor to donor and from day to day. The efficiency of two recovery methods, wet and dry swabbing and minitaping, was compared. The results indicate the tapelift method gave higher DNA recovery. This study also examined the secondary transfer of salivary DNA from skin to fabrics. Cotton and polyester give higher DNA transfer than leather.

Sexual assault statistics from the Republic of Ireland for 2004-2005.

The Republic of Ireland, like all other countries, has strict laws governing the crimes of rape and sexual assault. Victims of such assaults are treated in sexual assault treatment units where evidential material is gathered and forwarded to the forensic science laboratory (FSL). This paper represents the first published study from the Republic of Ireland of the time, day and month most frequently encountered in sexual assault cases presented to the FSL. In addition, the study examines the location and nature of the assault, together with such factors as the age of the victim, relationship to the suspect and degree to which the victim has a clear recollection of the events. The study covers information from 890 cases submitted to the FSL in the time period January 2004 to December 2005. The most common age category of victim was 16-30, the most likely time of occurrence was Saturday night/Sunday morning during the summer months of June, July or August. The assailant will most likely be known to the victim even if only recently met. Loss of memory mainly associated with the consumption of alcohol was a significant factor in many of the cases. The figures were compared to international studies with no significant differences between our findings and other studies. We also compared our results to a similar study in 1995-1996 and found little difference except for the number of the victims who were non-Irish nationals: 3% in the 1995-1996 study but by 2004-2005 that figure had risen to 11%.

Drug smuggling using clothing impregnated with cocaine.

A case study is presented where a woman travelling from South America to the Republic of Ireland was detained at Dublin Airport and articles of clothing she had in her luggage were found to be impregnated with cocaine. The study shows that the amount of powder recovered from the garments was approximately 14% of the total weight of the garments. The cocaine was in the form of cocaine hydrochloride and the purity was approximately 80%. An examination of the garments under filtered light highlighted the areas exposed to cocaine and indicated that the method of impregnation was by pouring liquid containing cocaine onto the clothing.

The reactivity of gamma-hydroxybutyric acid (GHB) and gamma-butyrolactone (GBL) in alcoholic solutions.

In this work the stability of GBL (gamma-butyrolactone) and GHB (gamma-hydroxybutyric acid) in alcoholic media was studied. Under acidic conditions the GBL will react with ethanol or methanol to give the corresponding ethyl and methyl esters of GHB. It can be seen that ester formation is dependent on the type of alcohol, the alcohol content of the solution, and the pH of the solution. Under the same conditions it was shown that GHB does not give rise directly to the corresponding ester when merely in the presence of an alcohol; however the ester will be formed if the conditions are present for conversion of GHB to GBL followed by subsequent reaction with alcohol. In alcoholic beverage samples spiked with GBL the expected conversion to GHB occurred, and the formation of the ethyl ester of GHB was also seen in some samples. Wine samples were analyzed for the presence of the ethyl ester of GHB, and the effect of adding GHB/GBL to hot beverages was studied.