Research potential and limitations of trace analyses of cremated remains

Human cremation is a common funeral practice all over the world and will presumably become an even more popular choice for interment in the future. Mainly for purposes of identification, there is presently a growing need to perform trace analyses such as DNA or stable isotope analyses on human remains after cremation in order to clarify pending questions in civil or criminal court cases. The aim of this study was to experimentally test the potential and limitations of DNA and stable isotope analyses when conducted on cremated remains.For this purpose, tibiae from modern cattle were experimentally cremated by incinerating the bones in increments of 100 °C until a maximum of 1000 °C was reached. In addition, cremated human remains were collected from a modern crematory. The samples were investigated to determine level of DNA preservation and stable isotope values (C and N in collagen, C and O in the structural carbonate, and Sr in apatite). Furthermore, we assessed the integrity of microstructural organization, appearance under UV-light, collagen content, as well as the mineral and crystalline organization. This was conducted in order to provide a general background with which to explain observed changes in the trace analyses data sets. The goal is to develop an efficacious screening method for determining at which degree of burning bone still retains its original biological signals. We found that stable isotope analysis of the tested light elements in bone is only possible up to a heat exposure of 300 °C while the isotopic signal from strontium remains unaltered even in bones exposed to very high temperatures. DNA-analyses seem theoretically possible up to a heat exposure of 600 °C but can not be advised in every case because of the increased risk of contamination. While the macroscopic colour and UV-fluorescence of cremated bone give hints to temperature exposure of the bone's outer surface, its histological appearance can be used as a reliable indicator for the assessment of the overall degree of burning.     

A comparison of penetration and damage caused by different types of arrowheads on loose and tight fit clothing

Bows and arrows are used more for recreation, sport and hunting in the Western world and tend not to be as popular a weapon as firearms or knives. Yet there are still injuries and fatalities caused by these low-velocity weapons due to their availability to the public and that a licence is not required to own them. This study aimed to highlight the penetration capabilities of aluminium arrows into soft tissue and bones in the presence of clothing. Further from that, how the type and fit of clothing as well as arrowhead type contribute to penetration capacity. In this study ballistic gelatine blocks (non-clothed and loose fit or tight fit clothed) were shot using a 24 lb weight draw recurve bow and aluminium arrows accompanied by four different arrowheads (bullet, judo, blunt and broadhead).The penetration capability of aluminium arrows was examined, and the depth of penetration was found to be dependent on the type of arrowhead used as well as by the type and fit or lack thereof of the clothing covering the block. Loose fit clothing reduced penetration with half of the samples, reducing penetration capacity by percentages between 0% and 98.33%, at a range of 10 m. While the remaining half of the samples covered with tight clothing led to reductions in penetration of between 14.06% and 94.12%.The damage to the clothing and the gelatine (puncturing, cutting and tearing) was affected by the shape of the arrowhead, with the least damaged caused by the blunt arrowheads and the most by the broadhead arrows. Clothing fibres were also at times found within the projectile tract within the gelatine showing potential for subsequent infection of an individual with an arrow wound.Ribs, femur bones and spinal columns encased in some of the gelatine blocks all showed varying levels of damage, with the most and obvious damage being exhibited by the ribs and spinal column.The information gleaned from the damage to clothing, gelatine blocks and bones could potentially be useful for forensic investigators, for example, when a body has been discovered with no weapons or gunshot residue present.     

Application of the discriminant analysis for the assessment of human somatotype using the long bones of extremities

Measurements were made on the basis of the osteological collection of the chair for anthropology, Moscow State University (70 cases), and on the basis of a series of skeletons (10 cases) from among burial places of the Novospassk Monastery (males aged above 18-20). Eleven sizes of Martin program (length, diaphysis circumference and epiphysis width) were fixed onto the humerus, radial, femoral and shin bones. Simultaneously, the development of the osseous relief elements in the above bones (a total of 18 signs in each skeleton) was evaluated by Fedosova program. The data was processed by SPSS. Discriminative analysis was used as a basis to work out a diagnostic model that can be used to determine a somatotype by the humerus, radial and femoral bones. The classification accuracy is 75%. The method should be applied in those cases, when the appropriate bones are available. If the available combination of bones is different from the above, the routine method is recommended for use, i.e. determination of a somatotype by the skeleton massiveness.     

Forensic medical expertise on burned bone remains

The series of 1138 cadaveric humerus and femurs of people of both sexes who died at the age of 17-91 years and 468 animal bones (cow, pig, sheep) was studied. Bones were burned (experimentally) at various temperature values and in different conditions. Investigations were carried out using osteometric, microscopic, microroentgenographic and mathematical methods. Species identification as well as sex and age determination using burned bone remains are possible regardless of the level of their burning. Regression equations to calculate victim's stature according to fragments of burned bones were received.     

Changes in illicit cocaine hydrochloride processing identified and revealed through multivariate analysis of cocaine signature data

For nearly 30 years, the methods utilized in illicit cocaine hydrochloride production have remained relatively consistent. Cocaine hydrochloride is typically produced one kilogram at a time. As a result, each individual kilogram is unique and distinct from other kilograms in any particular seizure based on the total alkaloid profile, occluded solvent profile, and isotopic signature. Additionally, multi-kilogram cocaine seizures are often comprised of cocaine from several different coca growing regions. There has been a documented shift in this type of processing based on the recent analysis of a large cocaine seizure in the Eastern Pacific. Signature analyses of samples from 21 kg randomly selected from a 517 kg seizure were virtually identical. Triplicate analyses of each sample via gas chromatography with flame ionization detection, static headspace gas chromatography mass spectrometry, and isotope ratio mass spectrometry were completed. An initial outlier evaluation of the data and an in-depth univariate analysis indicated there was no statistically significant difference among the 21 samples at the 95% confidence interval. Principal components analysis did reveal consistent minor deviations between the samples and known authentic data from the Nariño coca growing region of Colombia. These deviations were only observed on the latter principal components and could be explained by differences in solvent selection during cocaine hydrochloride processing. Chemical analyses in addition to a thorough statistical evaluation suggest a shift in the traditional small-batch method of cocaine processing to a multi-kilogram, high throughput approach.     

The age estimation of blood stains up to 30 days old using visible wavelength hyperspectral image analysis and linear discriminant analysis

A novel application of visible wavelength hyperspectral image analysis has been applied to determine the age of blood stains up to 30 days old. Reflectance spectra from selected locations within the hyperspectral image, obtained from a portable instrument, were subjected to spectral pre-processing. This was followed by the application of a linear discriminant classification model, making estimations possible with an average error of ± 0.27 days for the first 7 days and an overall average error of ± 1.17 days up to 30 days. This is also the first reported study of the determination of the age of fresh blood stains (less than one day old) with an error of ± 0.09 h. The studies have been made under controlled conditions and represent, at this stage, proof of concept results but also are the most accurate age estimation results for measurements between 0 and 30 days reported to date. The results are consistent with well-established kinetic processes suggesting that the pre-processing stages described are revealing spectroscopic changes which are reliably following the time dependent oxidation of HbO₂. The potential for parameterisation of environmental factors to make the method generally applicable at crime scenes is discussed, along with the developments required to further improve classification and to make the instrument genuinely portable.     

Different skeletal elements as a source of DNA for genetic identification of Second World War victims

To this day process of identification of missing persons from skeletonized human remains with help of forensic genetics proves to be complex and challenging. The success rate of genetic identification in bones strongly depends on a combination of various factors, most importantly environmental factors and post-mortem interval. Furthermore, there are individual-specific factors that affect DNA preservation, such as race, gender, age and type of skeletal elements. The goal of our study was to optimize sampling process through determining which skeletal elements are superior in their preservation of DNA in 70-yearold skeletons belonging to victims of Second World War. We sampled different types of bones and teeth from three such skeletons found in Slovenian hidden mass grave Huda jama, 56 elements from each respective skeleton, together 168 elements. With the help of parameters, such as quantity of DNA, degradation rate and typing success, we tried to find the best types of elements to identify the victims. Prior to powdering bones and teeth, we removed contaminants. We decalcified 0.5 g bone and tooth powder followed by extraction and purification of DNA using Biorobot EZ1 (Qiagen). Quantification of obtained nuclear DNA was carried out using PowerQuant kit (Promega) and autosomal STR typing using ESSplex SE QS kit (Qiagen). Best parameters to assess skeletal elements that are superior in their DNA preservation were quantity of DNA and number of successfully typed STR loci. Metacarpal and metatarsal bones proved to be the best, followed by intermediate cuneiform, first distal foot phalanx, talus, petrous bone and tibia. We also created elimination database for persons involved in exhumation, anthropological and genetic analyses and exclude potential contamination.     

Development and validation of highly selective screening and confirmatory methods for the qualitative forensic analysis of organic explosive compounds with high performance liquid chromatography coupled with (photodiode array and) LTQ ion trap/Orbitrap mass spectrometric detections (HPLC-(PDA)-LTQOrbitrap)

An LTQ-Orbitrap FTMS is a new (hybrid) mass spectrometric (MS) analyzer. It allows for the acquisition of full scan MSⁿ (n-stage fragmentations, n = 1 − n) spectra with the linear ion trap detector (LTQ) at high speed and/or with the Fourier Transform-detector (Orbitrap) with ultra high mass resolution (> 60,000 at m/z < 400 amu) and high mass accuracy (≤ 1 ppm with internal calibration). In addition it may be coupled with liquid chromatography (LC) with photo diode array (PDA) detection.Two methods for the forensic screening and confirmation of all common trace explosives in post-blast residues have been developed on this instrument using atmospheric pressure chemical ionization (APCI). In one run, the nitrogen-containing explosives are analyzed with the combination of “LC-(PDA)-APCI(−)-LTQ MS²/Orbitrap FTMS” (Method 1). In another run, peroxide explosives are analyzed with “LC-APCI(+)-LTQ MS²/Orbitrap FTMS” (Method 2).The performance of both methods has been validated according to procedures defined in the EU COMMISSION DECISION implementing Council Directive 96/23/EC concerning the performance of analytical methods and the interpretation of results (DC 2002/657/EC) and other standards (NEN 17025 and NEN 7777). The methods are highly selective due to the simultaneous utilization of the Orbitrap FTMS and LTQ MS², both of which are highly selective detectors Tested explosive compounds can be detected in the molecular ion form by the Orbitrap analyzer with minimal mass interference in different matrices when using an extremely narrow mass tolerance detection window (≤ 2 ppm). The identification of a detected compound follows an identification point system. Experimental results show that almost all explosive compounds meet the confirmation criteria (minimum 4 points) required for the positive identification by the DC 2002/657/EC.     

Palatal rugae as an individualising marker: reliability for forensic odontology and personal identification

Personal identification is based on the comparison between ante mortem and post mortem data which can be considered unique for each individual: palatal rugae represent a useful element for such a comparison, thanks to their apparent low variability with time and unique patterns. Literature however is scarce.This pilot study aims at assessing the reliability of palatal rugae in time and at developing an identification method based on their comparison. Two casts from the upper dental arch of 39 subjects were obtained in different periods of time; at their first cast, 85.2% of patients were less than 16 years old. The second cast was performed after a period of time which varied between 4 and 65 months later than the first cast. The first cast can be taken to simulate ante mortem information, the second post mortem information. Every cast was then digitised with a scanner. In the digital images the palatal rugae were highlighted by using Adobe® Photoshop® 7.0 software; each image was coded and a comparison between “simulated” ante mortem and post mortem data was performed. In all cases ante mortem and post mortem data from the same individual were correctly matched.The study seems to indicate that this technique is highly reliable and user friendly, even on subadults, where growth processes seem not to affect the specific morphology of palatal rugae.     

Determination of DNA yield rates in six different skeletal elements in ancient bones

Current sampling strategy for laboratories typing bones for human identification include samples obtained from femur, tooth and temporal bone. Latest studies suggest that the small bones of the hands and feet were very similar or even better in DNA yield. These bones can be easily sampled with a disposable scalpel and thus reduce potential DNA contamination. The aim of our study was to determine the suitability of metatarsals, metacarpals and phalanges for genetic identification. 48 bone samples from 8 different skeletons (six from 18^th century and two from 3rd century) were obtained from 5 archaeological sites in Slovenia. In each skeleton, 6 different skeletal elements were sampled (temporal bone, molar, femur, metacarpal bone, metatarsal bone and proximal phalanx of the hand), and strict precautions followed to prevent contamination. Half of gram of bone powder was decalcified using full demineralization extraction method. The DNA was purified in a Biorobot EZ1 (Qiagen), DNA content determined with the PowerQuant kit (Promega), and autosomal STR typing performed with the Investigator ESSplex Plus kit (Qiagen). Up to 8.75 ng DNA/g of powder was obtained from samples analyzed. The highest yields were detected in temporal bone and the lowest in femur. The success rate of STR typing was evaluated according to the number of successfully typed loci and a strong correlation between the success rate of STR typing and the amount of extracted DNA was confirmed. For all eight skeletons full consensus genetic profiles were determined from skeletal elements analyzed. Our findings suggest it would be suitable to include metatarsal and metacarpal bones in sampling strategy for human identification although further research is needed to substantiate the findings of this study.     

Recovery of human DNA profiles from poached deer remains part 2: Improved recovery protocol without the need for LCN analysis

Although poaching is a common wildlife crime, the high and prohibitive cost of specialised animal testing means that many cases are left un-investigated. We previously described a novel approach to wildlife crime investigation that looked at the identification of human DNA on poached animal remains (Tobe, Govan and Welch, 2011). Human DNA was successfully isolated and amplified from simulated poaching incidents, however a low template protocol was required which made this method unsuitable for use in many laboratories. We now report on an optimised recovery and amplification protocol which removes the need for low template analysis.Samples from 10 deer (40 samples total — one from each leg) analysed in the original study were re-analysed in the current study with an additional 11 deer samples. Four samples analysed using Chelex did not show any results and a new method was devised whereby the available DNA was concentrated. By combining the DNA extracts from all tapings of the same deer remains followed by concentration, the recovered quantity of human DNA was found to be 29.5 pg ± 43.2 pg, 31 × greater than the previous study. The use of the Investigator Decaplex SE (QIAGEN) STR kit provided better results in the form of more complete profiles than did the AmpF?STR® SGM Plus® kit at 30 cycles (Applied Biosystems). Re-analysis of the samples from the initial study using the new, optimised protocol resulted in an average increase of 18% of recovered alleles. Over 17 samples, 71% of the samples analysed using the optimised protocol showed sufficient amplification for comparison to a reference profile and gave match probabilities ranging from 7.7690 × 10^? 05 to 2.2706 × 10^? 14.The removal of low template analysis means this optimised method provides evidence of high probative value and is suitable for immediate use in forensic laboratories. All methods and techniques used are standard and are compatible with current SOPs. As no high cost non-human DNA analysis is required the overall process is no more expensive than the investigation of other volume crime samples. The technique is suitable for immediate use in poaching incidents.     

Reliability of a two-dimensional footprint measurement approach

Although footprint evidence can be taken from the scene of a crime, the science underpinning such measurement in forensic science has not been fully explored.A literature search revealed various measuring approaches, all of which demonstrated either little or no measurement rigour in terms of reliability. The aim of this study was to apply a robust measurement approach for testing the reliability of two-dimensional footprint impressions.Three dynamic and three static footprints were taken from the right foot of thirty female and thirty one male volunteers using the ‘Inkless Shoeprint Kit’. The images were digitised. Lengths, widths and angles were measured using a selection of currently employed methods.An investigation of the reliability of the chosen measuring method suggested high intra-rater agreement: for example, the length measurement suggested an intraclass correlation coefficient (ICC) 0.99, 95% Confidence Interval (CI) ? 0.28 to 0.01, standard error of measurement (SEM) 0.07, Limits of Agreement (LOA) ? 0.91 to 0.65.Inter-rater reliability between three operators was also high: SEM ranged from 0.05 mm to 0.07 mm, ICC 0.99.Our study has established a reliable two-dimensional measuring technique that could be used for footprint comparison in further research.     

Transfer of fibres on the hands of living subjects and their persistence during hand washing

Textile fibres were transferred to the hands of ten living subjects and their persistence was determined after hand washing. Average number of fibres transferred was 300 ± 133 (female 288 ± 92, male 311 ± 163) per 100 cm² hand area in the 100 experiments. However the number of fibres transferred was not gender dependent but individual dependent. The hand texture of subjects was compared with the number of fibres transferred but the relationship was not observed. The number of fibres transferred varied significantly for the 10 repeated experiments performed under the same conditions for the same subject.The subjects were then asked to wash their hands with water. One test group washed their hands with standing water, and the other with running tap water. Afterwards, the number of fibres remaining on the test subjects' hands were investigated. Migration of the fibres on the surface of the observed hands did occur but total loss of transferred fibre after hand washing did not occur. The average number of fibres remaining per 100 cm² hand area was 14 ± 10 (range = 3–72) for hand washing with standing water, and 10 ± 12 (range = 0–79) for washing with running tap water. The results of this study show the possibility of finding fibres on the hands of a person involved in a criminal case even after hand washing before fibre collection.     

Detection of acute fentanyl exposure in fresh and decomposed skeletal tissues part II: The effect of dose–death interval

The effects of dose–death interval on the detection of acute fentanyl exposure in fresh and decomposed skeletal tissues (marrow and bone), by automated enzyme-linked immunosorbent assay (ELISA) are described. Rats (n = 14) were administered fentanyl acutely at a dose of 0 (n = 2) or 60 μg/kg (n = 12) by intraperitoneal injection, and euthanized within 20, 45, 135, or 225 min. Femora and tibiae were extracted from the fresh corpses and marrow was isolated from the femoral and tibial medullary cavities. The remains were then allowed to decompose outdoors to the point of complete skeletonization, and vertebrae, pelvi and miscellaneous (humeri and scapulae) were recovered for analysis. In all cases, bones were cleaned in alkaline solution and then ground into a fine powder. Marrow was homogenized in alkaline solution. Fentanyl was extracted from ground bone by methanolic extraction. Extracts were adjusted to pH 6 and analyzed by ELISA. Perimortem heart blood was also collected and diluted in phosphate buffer prior to screening by ELISA. The effect of tissue type on ELISA response was examined through determination of binary classification test sensitivity and the relative decrease in absorbance (%DA, drug-positive tissues vs. drug-free controls) in each tissue type. Overall, the %DA varied significantly between extracts from different skeletal tissues at a given dose–death interval, according to the general order of marrow > decomposed bone > fresh bone. Binary classification test sensitivity values for fentanyl in marrow, fresh epiphyseal (femoral and tibial) bone, fresh diaphyseal (femoral and tibial) bone, decomposed vertebrae, decomposed pelvic bone, and decomposed miscellaneous bone were 67–100%, 0–33%, 0–33%, 0–67%, 0–67% and 0–33%, respectively, over all dose–death intervals. Although group mean %DA values showed a strong negative correlation with dose–death interval in marrow, fresh epiphyseal bone, decomposed vertebrae, pelvic and miscellaneous bone (r = ?0.989, ?0.930, ?0.955, ?0.903, and ?0.974, respectively), the high variability in both fresh and decomposed bone precluded differentiation of the dose–death intervals based on %DA value alone. Overall, the results suggested that the type of skeletal tissue sampled may not be as important as the amount of residual marrow remaining in skeletonized remains.     

Evaluation of the composition of street cocaine seized in two regions of Brazil

This work evaluates cocaine purity and the concentration ranges of adulterants and inorganic constituents for 31 street cocaine samples seized in two different regions of Brazil from July 2008 to May 2010. Cocaine and adulterants, such as caffeine, lidocaine and benzocaine, were quantified by Gas chromatography–mass spectrometry (GC–MS), and the inorganic constituents were determined by Inductively Coupled Plasma-Optical Emission Spectrometry (ICP-OES) and ion chromatography (IC). The cocaine concentrations in the samples seized in the Amazonas state (AM samples) ranged from 154 to 978 mg g^? 1, and these samples did not contain any of the adulterants studied. The cocaine concentrations in the samples seized in the Minas Gerais state (MG samples) ranged from 63.9 to 753 mg g^? 1. Caffeine was the main adulterant found in 76% of the MG samples, ranging in concentration from 5.5 to 645.3 mg g^? 1. Lidocaine was found in 66.7% of the MG samples, with concentrations ranging from 16.3 to 576.7 mg g^? 1. Benzocaine was found in only one MG sample, at a concentration of 84.8 mg g^? 1. Fourteen elements were identified by ICP-OES, and a wide variation was observed in the concentrations of Ca, Mg, Na, P, Al, Fe, Mn and Zn. Pearson Product–moment Correlations between the analytes allowed the constituents to be associated with the chemicals used in the manufacturing of cocaine and with some common diluents. The study of the purity of cocaine and the presence and concentration of adulterants and inorganic constituents is important because the latter can have deleterious effects on health.     

Determination of amphetamine-type stimulants,ketamine and metabolites in fingernails by gas chromatography–mass spectrometry

A gas chromatography–mass spectrometry (GC–MS) method was developed and validated for the simultaneous qualification and quantification of methamphetamine (MA), amphetamine (AP), 3,4-methylenedioxy-N-methylamphetamine (MDMA), 3,4-methylenedioxy-N-amphetamine (MDA), ketamine (KET) and norketamine (NKT) in fingernails. Fingernail samples (20 mg) were washed with distilled water and methanol, digested with 1.0 M sodium hydroxide at 95 °C for 30 min, and then extracted with ethyl acetate. Extract solutions were evaporated to dryness, derivatized using heptafluorobutyric anhydride (HFBA) at 60 °C for 30 min, and analyzed by GC–MS. The linear ranges were 0.1–20.0 ng/mg for AP, MDMA and NKT, 0.2–20.0 ng/mg for MA and MDA, and 0.4–20.0 ng/mg for KET, with the coefficients of determination (r² ≥ 0.9989). The intra- and inter-day precisions were within 7.1% and 10.6%, respectively. The intra- and inter-day accuracies were ?10.9% to 0.8% and ?4.3% to 4.5%, respectively. The limits of detections (LODs) and the limits of quantifications (LOQs) for each analyte were lower than 0.094 ng/mg and 0.314 ng/mg, respectively. The recoveries were in the range of 72.3–94.9%. The average fingernail growth rates of two subjects for three years and six subjects for two months were 3.12 mm/month and 3.16 mm/month, respectively. The method proved to be suitable also for the simultaneous detection and quantification of MA, MDMA, KET and their metabolites in fingernails.     

Rapid GC–MS confirmation of amphetamines in urine by extractive acylation

Amphetamine and related derivatives are widely abused central- and psychostimulants. Detection of certain derivatives, such as methcathinone, by commonly available immunoassay screening techniques is insufficient. Multi-analyte confirmations for amphetamine type stimulants are therefore required, but traditional gas chromatography–mass spectrometry methods necessitate lengthy analytical procedures with prolonged sample turn-around times. A validated rapid GC–MS assay for urinary confirmation of amphetamine, methamphetamine, methcathinone, ephedrine, norephedrine, methylenedioxyamphetamine, methylenedioxymethamphetamine, methylenedioxyethylamphetamine and N-methyl-1-(3,4 methylenedioxyphenyl)-2-butanamine is reported. The method entailed in situ derivatization of urine specimens by extractive acylation with pentafluoropropionic anhydride, followed by rapid chromatography on a microbore capillary column. Analytes were separated in less than 3 min and quantified simultaneously by selected-ion monitoring using stable isotope substituted internal standards. The total instrument cycle-time was 6 min per sample. The limits of detection were between 1.5 ng/mL and 6.25 ng/mL for the various analytes. Intermediate precision and accuracy were in the range of 6.3–13.8% and 90.5–107.3% for the respective analytes at the lower limit of quantitation, and between 5.8–12.6% and 95.4–103.1% for the high control. Long-term storage of methcathinone positive specimens at ?20 °C proved insufficient stability of this analyte. The proposed assay is precise and accurate for confirmation of amphetamine and derivatives in urine. The complementary approach of extractive-derivatization and fast GC–MS analysis is especially applicable in routine clinical settings where reduced sample turn-around times are required. Further investigation of cathinone as a possible metabolite of methcathinone is warranted, based on results from analyzed authentic urine samples.     

Age estimation by pulp/tooth area ratio in canines: Cameriere's method assessed in an Indian sample using radiovisiography

Age estimation of an individual whether living or dead is an intimidating task in forensic investigations. Since teeth are more resistant to most peri- and post-mortem changes, they are frequently used for identification and age estimation when skeletal remains are in poor condition. However, most methods are destructive and warrant extraction of teeth which is not feasible in living individuals. Cameriere's et al. put forth a radiographic method of age estimation by pulp to tooth area ratio (AR) in canines and revealed a linear regression between age and the AR. In the present study, we estimated the AR in 456 canines (upper, lower and both) in an Indian sample (114 males and 114 females) using radiovisiography technique. Linear regression equations were derived for upper canine, lower canine and both using the AR to estimate chronological age. Additionally, the efficacy of these equations was also evaluated in younger age group (<45 years). The formulas derived, i.e., age = 96.795 ? 513.561x₁ (Eq. (1)) for upper canine, age = 88.308 ? 458.137x₂ (Eq. (2)) for lower canine and age = 99.190 ? 283.537x₁ ? 306.902x₂ + 400.873x₁x₂ (Eq. (3)) for both the canines were applied to predict the chronological age. The mean value of residuals using these regression equations ranged from 4.28 to 6.39 years with upper canine equation generally giving a precise result. When these equations were applied for younger ages (<45 years), the regression equation derived from both canines gave a better result (mean residual 2.70 years). Overall these equations were better able to predict the age in younger ages, i.e., up to 45 years.     

An investigation into the enhancement of fingermarks in blood on paper with genipin and lawsone

The abilities of two natural products, genipin and lawsone, to enhance blood contaminated fingermarks on papers of various porosities and colour were investigated and compared to the routinely used amino acid reagents, ninhydrin and 1,8-diazafluoren-9-one (DFO).Fingermarks in blood were deposited as a split depletion series on various paper types and colours for ageing periods of 6 weeks, 4 weeks, 2 weeks and 1 week before enhancement. The developed marks were observed under different lighting conditions, recorded and graded by way of attributing quantitative data to each series.Results indicated that while genipin showed some potential as a reagent for the enhancement of latent fingermarks, it displayed no suitability for the enhancement of fingermarks in blood on paper. Lawsone also failed to successfully enhance either type of fingermark. Upon comparison of the results with those of ninhydrin and DFO it was found that ninhydrin displayed the highest success rate of development of these marks.     

Fast quantification of 11-nor-Δ9-tetrahydrocannabinol-9-carboxylic acid (THCA) using microwave-accelerated derivatisation and gas chromatography–triple quadrupole mass spectrometry

A rapid and sensitive determination of cannabinoids in urine is important in many fields, from workplace drug testing over toxicology to the fight against doping. The detection of cannabis abuse is normally based on the quantification of the most important metabolite 11-nor-Δ9-tetrahydrocannabinol-9-carboxylic acid (THCA) in urine. In most fields THCA needs to be present at a concentration of exceeding 15 ng/mL before a positive result can be reported.The method described in this paper, combines a 4 min GC–MS/MS method with a fast sample preparation procedure using microwave assisted derivatisation in order to complete the quantification of THCA in urine in 30 min, using only 1 mL of urine.The method is selective, linear over the range 5–100 ng/mL and shows excellent precision and trueness and hence, the estimated measurement uncertainty at the threshold level is small. The method also complies with applicable criteria for mass spectrometry and chromatography. Therefore the method can be used for rapid screening and confirmatory purposes.