A study of illicit cocaine seizure classification by pattern recognition techniques applied to metal data

Fifteen metallic species, silver (Ag), aluminum (Al), calcium (Ca), cadmium (Cd), chromium (Cr), copper (Cu), iron (Fe), potassium (K), magnesium (Mg), manganese (Mn), sodium (Na), nickel (Ni), lead (Pb), strontium (Sr) and zinc (Zn), were determined in 46 cocaine samples confiscated by the Spanish police in Galicia (northwest Spain). Classification of these cocaine samples according to their geographic origin (Colombia and Venezuela) was achieved by the application of pattern recognition techniques to the metallic content data. Cocaine samples, around 0.5 g, were directly dissolved in 2 mL of 35.0% (v/v) HNO3, diluted to 10 mL with ultrapure water. The metals were quantified by means of electrothermal atomic absorption spectrometry (Ag, Al, Cd, Cr, Cu, Mn, Ni, Pb and Sr), flame atomic absorption spectrometry (Ca, Fe, Mg and Zn), and flame atomic emission spectrometry (K and Na). Results show that two geographic origins can be established through the presence of trace and major elements.     

Lower limits of detection of synchrotron radiation high-energy X-ray fluorescence spectrometry and its possibility for the forensic application for discrimination of glass fragments

Synchrotron radiation high-energy X-ray fluorescence (SR-XRF) analysis utilizing 75.5keV X-ray radiation from beam-line BL37XU at Super Photon Ring 8GeV (SPring-8), a third-generation synchrotron facility, was found to have advantages for forensic discrimination of glass samples. The lower limits of detection (LLD) for calibration curves were at the picogram level for Ba, Ce, and Sm and at the 10pg level for Sr, Zr, Sn, and Hf. The spectrum of NIST SRM 612 glass reference material demonstrated K-line peaks of 31 elements including rare-earth elements, and the relative standard deviations (R.S.D.) of all the measured elements except Ca were less than 9.7%. Fragments of collected sheet glass were used as samples for investigating the application of this technique to forensic analysis. Several trace elements such as Pb, Rb, Sr, Zr, La, Ce, and Hf were detected in the spectra of the samples, and these elements could be used as indexes to characterize the glass samples. But the "lower limits of detection (LLD)" of each element were not examined enough. In this report, these limits by synchrotron radiation X-ray spectrometry were clarified. By these results, this technique should provide an effective approach to the nondestructive discrimination of small glass fragments in the field of forensic science.     

Voltammetric determination of Δ9-THC in glassy carbon electrode: An important contribution to forensic electroanalysis

Teeth are recently drawing attention for their potential as biological modeling investigation samples due to their ability to be collected and their slow substance metabolism. There is no active metabolism of elements after the completion of dentin. Dentin is surrounded by enamel and cementum, and is not affected by the oral environment. Therefore, the amount of trace elements in dentin may change with age, and this is considered to be a reliable biological load index. The objectives in this study are to demonstrate concentrations of elements in the dentin of healthy Japanese subjects by sex and age, and to reveal the relationship between element levels and age. 121 healthy teeth samples were extracted due to periodontal disease or orthodontic treatment. Each tooth was sliced from the crown to the root apex into 0.5-1mm thickness, then enamel, cementum, and the pulp were removed; the dentins were used as samples. The concentration of 10 trace elements (B, Mn, Co, Cu, Zn, Rb, Sr, Mo, Cd, and Pb) in the dentin was measured using inductively coupled plasma mass spectrometer (ICP-MS). The differences Co and Pb in the dentin between men and women were significant (p<0.01). Significant positive correlation was observed between B, Co, Cu, Zn, Sr and Pb concentrations in the dentin and age (p<0.001). The results of the present study suggest that human dentin is an appropriate substance for relativity with sex and age at further future research.     

应用SME/EDX和ICP-AES检测元素成份判定致伤工具

目的应用扫描电镜／能谱联合分析仪(Scanning electron microscopy&Energy dispersive X-ray apparatus SEM／EDX)和电感耦合原子发射等离子光谱(inductively coupled plasma-atom emission spectrometer ICP-AES)对金属致伤工具本身及所致创口残留物元素成分分析，探讨两者在推断认定此类工具的应用条件及价值。方法镀层和普通铁质工具在乳猪皮肤各致创5例，SEM／EDX对创口内遗留金属颗粒元素检测；用标准样品检测实验方法的精确度；普通铁质工具于刀背、刀刃处各取5个样本，ICP-AES测定元素成分与含量。结果镀锌工具所致创口中存在单一含有锌的金属颗粒，镀黄铜工具则同时含有锌和铜，未发现其它元素；不锈钢或普通铁质菜刀创口中，发现同时含有铁、铬、硅或铁、锰、硅的颗粒；除5号菜刀外同一把铁质菜刀在刀刃、刀背处元素含量无明显差别；ICP-AES分析表明不锈钢菜刀之间在铬、锰、硅、铜、钼和5号刀背部以及其他铁质菜刀在锰、硅元素含量差别具有显著意义，5号刀刃部锰、硅、钼、钛、磷、硫、镍元素RSD明显升高。结论SEM／EDX可以通过创口的检测对金属致伤工具进行种类的推断认定，ICP-AES则可在同种类致伤工具中进行相对同一的判定有应用价值。     

应用SEM/EDX和ICP-AES检测元素成份判定致伤工具

目的应用扫描电镜/能谱联合分析仪(Scanning electron microscopy & Energy dispersive X-ray apparatus SEM/EDX)和电感耦合原子发射等离子光谱(inductively coupled plasma-atom emission spectrometer ICP-AES)对金属致伤工具本身及所致创口残留物元素成分分析,探讨两者在推断认定此类工具的应用条件及价值.方法镀层和普通铁质工具在乳猪皮肤各致创5例,SEM/EDX对创口内遗留金属颗粒元素检测;用标准样品检测实验方法的精确度;普通铁质工具于刀背、刀刃处各取5个样本,ICP-AES测定元素成分与含量.结果镀锌工具所致创口中存在单一含有锌的金属颗粒,镀黄铜工具则同时含有锌和铜,未发现其它元素;不锈钢或普通铁质菜刀创口中,发现同时含有铁、铬、硅或铁、锰、硅的颗粒;除5号菜刀外同一把铁质菜刀在刀刃、刀背处元素含量无明显差别;ICP-AES分析表明不锈钢菜刀之间在铬、锰、硅、铜、钼和5号刀背部以及其他铁质菜刀在锰、硅元素含量差别具有显著意义,5号刀刃部锰、硅、钼、钛、磷、硫、镍元素RSD明显升高.结论SEM/EDX可以通过创口的检测对金属致伤工具进行种类的推断认定,ICP-AES则可在同种类致伤工具中进行相对同一的判定有应用价值.     

电感耦合等离子体质谱法检测电流损伤皮肤中金属元素

目的探讨应用电感耦合等离子体质谱(inductively coupled plasma mass spectrometry,ICP-MS)技术检测电流损伤皮肤中金属元素的可行性,建立检测电流损伤皮肤中金属元素的方法。方法用黄铜、紫铜、铝、铁电极材料以220V交流电电击家兔后肢,ICP-MS对电流损伤皮肤中金属元素进行检测。结果与对照组比较:黄铜电击组皮肤中的Cr、Ni、Cu、Zn、Pb含量升高(P0.05),紫铜电击组皮肤中的Cr、Cu、Pb含量升高(P0.05),铝电击组皮肤中的Al、Cr、Mn、Co、Ni、Cu、Pb含量升高(P0.05),铁电击组皮肤中的Cr、Mn、Fe、Ni含量升高(P0.05)。不同电极材料电击后皮肤中元素种类及含量也存在明显差异。结论ICP-MS可作为检测电流损伤皮肤中金属元素的有效方法,且可应用于触电材料的推断。     

Identify the injury implements by SEM/EDX and ICP-AES

The forensic investigator is frequently confronted with the discrimination and deduction of injury implements, which is one of the most important physical testimonies in courts. The usual method used in actual cases is from points of morphology. In the forensic discrimination of injury implements, such as metal implements, the analysis and comparison of elements are expected to provide excellent results, and simultaneous multi-elemental analysis is required to analyze various kinds of elements. This study was designed to establish discrimination and deduction of metal injury implements by scanning electron microscope/energy disperse X-ray microanalyzer (SEM/EDX) and inductively coupled plasma atomic emission spectrometry (ICP-AES). Examined metal particles in five wounds made on the skin of domestic pigs, respectively, using Cu-Zn or Cr-Ni coated and carbon steel kitchen implements by EDX. For carbon steel kitchen implements, analyzed five samples from the back and blade separately in the contents and varieties of elements by ICP-AES. In the wounds by the coated implements, the special particles only containing Cu, Zn or Cr, Ni were found. In the wounds by carbon steel kitchen implements, the particles containing Fe, Cr, Si or Fe, Mn, Si were found. The differences of contents of elements between the back and blade was no significant except No. 5 for carbon steel kitchen implements, and the significant differences of elements exited in Cr, Mn, Si, Cu, Mo among the stainless kitchen knives, Mn, Si among the other kitchen implements and for the blade of No. 5 knife, relative standard deviations (R.S.D.s) were significantly different in Mn, Si, Mo, Ti, S, P, Ni. Using EDX to examine the particles in wounds can deduce the categories of metal injury implements, and we can still deduce the different implements in the same category by ICP-AES.     

Levels of trace and major elements in illicit heroin

Ten elements, aluminum (Al), barium (Ba), calcium (Ca), cadmium (Cd), copper (Cu), iron (Fe), magnesium (Mg), manganese (Mn), lead (Pb), and zinc (Zn) were analyzed in 44 illicit heroin samples from Southeast Anatolia, Turkey. Illicit heroin samples were dissolved in nitric acid using microwave oven and were quantified by electrothermal atomic absorption spectrometry (Cd and Pb) and inductively coupled plasma-atomic emission spectrometry (Al, Ba, Ca, Cu, Fe, Mg, Mn, and Zn). The most abundant element was calcium, 4050 to 14,200 microg/g, which could be ascribed to the use of lime in the manufacturing process and/or as diluting agent. Iron (180 to 1470 microg/g), aluminum (42 to 2280 microg/g), and zinc (160 to 210 microg/g) were found at moderately high levels, possibly because of the use of metal pots in the acetic anhydride cooking process and also for storage. Cadmium and lead concentrations were at the lowest measured levels. The amounts of magnesium, manganese, barium, and copper were in the range of 100 to 800 micro/g, 3 to 17 microg/g, 4 to 30 microg/g, and 2 to 46 microg/g, respectively.     

Extent of Groundwater Contamination Due to Leachate Migration Adjacent to Unlined Landfill Site of Delhi

The leachate and groundwater samples were collected from the 2 km radius of Ghazipur landfill site. The high levels of EC, TDS, Chloride, Nitrate, Sodium, Potassium, BOD, and COD were observed in the leachate and groundwater samples. In leachate, metal concentrations were found in the order as – Fe > Zn > Cu > Pb > Ni > Cr > Cd. In groundwater, Zn, Ni, and Cu ranged as 0–0.386 mg/l, 0–0.013 mg/l, and 0–0.027 mg/l, respectively whereas Cd, Cr, and Pb were found in trace amount. The study clearly indicates that the percolation of leachate from the landfill site results in the contamination of groundwater of the surrounding area.     

上海地区干尸形成的条件及机理

运用常规的尸体检验方法对干尸进行检验,根据季节、现场、尸体保存方法等探讨干尸形成的条件和机理。发现在上海温暖潮湿南方地区,干尸形成多见于气温较低、环境干燥季节,死亡前多有脱水和绝食经历,且伴有翻动尸体及通风等人为干预因素。     

Microbial metagenome profiling using amplicon length heterogeneity-polymerase chain reaction proves more effective than elemental analysis in discriminating soil specimens

The combination of soil's ubiquity and its intrinsic abiotic and biotic information can contribute greatly to the forensic field. Although there are physical and chemical characterization methods of soil comparison for forensic purposes, these require a level of expertise not always encountered in crime laboratories. We hypothesized that soil microbial community profiling could be used to discriminate between soil types by providing biological fingerprints that confer uniqueness. Three of the six Miami-Dade soil types were randomly selected and sampled. We compared the microbial metagenome profiles generated using amplicon length heterogeneity-polymerase chain reaction analysis of the 16S rRNA genes with inductively coupled plasma optical emission spectroscopy analysis of 13 elements (Al, B, Ca, Cu, Fe, K, Mg, Mn, Na, P, S, Si, and Zn) that are commonly encountered in soils. Bray-Curtis similarity index and analysis of similarity were performed on all data to establish differences within sites, among sites, and across two seasons. These data matrices were used to group samples that shared similar community patterns using nonmetric multidimensional scaling analysis. We concluded that while chemical characterization could provide some differentiation between soils, microbial metagenome profiling was better able to discriminate between the soil types and had a high degree of reproducibility, therefore proving to be a potential tool for forensic soil comparisons.     

Quantitative analysis of glasses used within Australia

An initial 134 glasses have been collected from eleven classifications of glass used within Australia. These include both local and imported glasses. Quantitative elemental analyses of the glasses have been determined using a scanning electron microscope equipped with an energy dispersive X-ray spectrometer. The current program provides for an elemental analysis for Na, Mg, Al, Si, P, S or Pb, Cl, K, Ca, Ba or Ti, V, Cr, Fe, Mn and Zn expressed as oxides, and has a sensitivity down to approximately 0.1%. The data for the six most commonly occurring elements, namely, Na, Mg, Al, Si, K and Ca, together with the refractive index are presented for each class of glass in terms of their mean value and standard deviation from the mean, and also in histogram form.     

Differentiation of bullet type based on the analysis of gunshot residue using inductively coupled plasma mass spectrometry

Porcine tissue samples shot with two different types of bullets, jacketed and nonjacketed, were collected in the fresh state and throughout moderate decomposition. Wound samples were microwave-digested and analyzed using inductively coupled plasma mass spectrometry (ICP-MS) to detect all elements present at measurable levels in gunshot residue (GSR). Elements detected included antimony (Sb), barium (Ba), and lead (Pb), which are considered characteristic of GSR, as well as iron (Fe) and copper (Cu). These five elements were used to differentiate shot tissue and unshot tissue, as well as tissue shot by the two different bullet types, both in the fresh state and throughout moderate decomposition. The concentrations of Cu, Sb, and Pb were able to distinguish the two bullet types in fresh tissue samples at the 95% confidence level. Cu and Pb were able to differentiate the bullet types throughout moderate decomposition at the 99% confidence level.     

微束X射线荧光光谱法检测电流损伤皮肤金属化

目的建立微束X射线荧光光谱（μ-probe X-ray fluorescence,μ-XRF）检测电流损伤皮肤金属化的方法。方法新西兰大白兔32只,随机分为黄铜电击组、紫铜电击组、铁电击组、铝合金电击组,每组8只。电极一极固定于左后腿中部,另一极固定于左前腿,建立电击模型。提取左后腿触电部位皮肤,以及对侧右后腿相应部位皮肤作为对照,应用μ-XRF光谱仪对电流损伤皮肤内金属元素进行测定。结果正常对照组皮肤中检测出磷、氯、钾、钙元素成分;在电击组皮肤中,除正常皮肤检出的元素外,黄铜电击组检测出铜、锌元素,紫铜电击组检出铜元素,铁电击组检出铁元素,铝合金电击组检出铝元素。渗透到电流损伤皮肤内的金属元素呈不均匀分布。结论μ-XRF光谱法检测皮肤金属化可作为诊断电流损伤的特征性指标,并可为触电材料的推断提供依据。     

The discrimination of automotive clear coats by pyrolysis-gas chromatography/mass spectrometry and comparison of samples by a chromatogram library software

Identification particles used for the purpose of the post-blast identification of explosives have a coding system based on the combination of metal oxides and their various concentrations. These materials are composed of the polymeric matrix, iron powder (ferromagnetic properties), UV light active dyestuff and various metal oxides in a various ratios. A suitable analytical method has to be used for an accurate characterization of these metal components in the particles in order to find the required information, i.e. to determine the place and the year of production and as the case may be, also the production batch of misused explosives. In this work, the method of microwave digestion and flame atomic absorption spectrometry (F-AAS) was developed for an accurate determination of Zn, Mg, Cu and Pb in a few novel types of identification particles and applied to their characterization. When using specific sample treatment (digestion with a mixture of nitric acid with hydrochloric or hydrofluoric acid), the 3 sigma limits of detection (LODs) for the determination of Zn, Mg, Cu and Pb in 5mg original samples were 1.9, 0.2, 1.3 and 2.4 mg g(-1), respectively. The signal suppression due to the presence of HNO3+HCl or HNO3+HF was observed for Zn; therefore, the calibration solutions had to be prepared exactly with the same acids as those used for the sample mineralization. The determination of Mg, Cu and Pb was free of interferences; hence a simple calibration curve method could be adopted for attaining accurate results. The accuracy was checked by comparison of the results with those obtained by means of independent inductively coupled plasma optical emission spectrometry (ICP-OES). Good precision values, as relative standard deviation, in the range of 1-5% were obtained. A total number of 71 samples was analysed and classified by multivariate methods to prove the suitability of the procedure proposed for the purpose of the identification of explosives.     

A serological and histological study of the Egyptian mummy 'Iset Iri Hetes' from the Ptolemaic period III-I B.C

Serological and histological examinations of the muscles of the calf of an Egyptian mummy dated between the third and first centuries B.C. were performed. Human protein was identified, the ABO phenotype was determined as type B, and morphological disruption of the cells was observed.     

Analysis of wrapped or cased object by a hand-held X-ray fluorescence spectrometer

Metals, alloys, and poisoned food were analyzed with a hand-held X-ray fluorescence (XRF) spectrometer, with a shield (wrapping or casing material) inserted between these objects and the spectrometer, in order to examine the possibility of analyzing the contents of packages. Elements such as Fe, Cr, Ni, Cu, Zn, Pb, Mo, and As were detected in the objects. The fluorescent intensity of each element in the object decreased exponentially as the thickness of the shield increased, and the degree of decrease depended on both the material of the shield and the energy of fluorescent X-rays. The thickness of the shield can be calculated by using the intensity ratio Fe Kbeta/Kalpha or Pb Lbeta/Lalpha when the object is iron or lead, or by using the intensity of the Compton scattering of incident X-rays. The original peak intensity, i.e. intensity without a shield, of an element in an object can be estimated with the thickness of the shield obtained. Because the original peak intensity is calculated using an exponential function of the thickness of the shield, calculation of the intensity ratio, e.g. Zn Kalpha/Cu Kalpha for brass, is effective for cancelling the estimation error for the thickness of the shield. The composition of brass and steel can be estimated with an error of less than 30% by using the intensity of the Compton scattering.     

In- and out-flows of elements in bones embedded in reference soils

Possible exchanges of elements between bone and the surrounding soil after being embedded underground for 2 years were estimated. Bone pieces were samples from human vertebrae without any treatments after resection. Sixteen elements were determined by atomic emission mass spectrometry. These were divided into three types; Type I, an in-flow in which elements increased, as in Fe, Al and Ba; type II, a balanced decrease in which changes were found in S, Mg and Zn; and type III, an out-flow in which elements, such as Ca and P, entered into bones from embedded soils. These exchanges depended on the varying nature of soils and also on the time underground. The exchanges were progressed in duration of the time after burial. Data obtained are possible references to judge the time-lapse after burial of bones in relating to characters of soils embedded, and to identify proper bone elements from containment elements.     

Trace Elemental Analysis of Titanium Dioxide Pigments and Automotive White Paint Fragments for Forensic Examination Using High‐Energy Synchrotron Radiation X‐Ray Fluorescence Spectrometry*

Abstract: High‐energy synchrotron radiation x‐ray fluorescence spectrometry (SR‐XRF) utilizing 116 keV x‐rays was used to characterize titanium dioxide pigments (rutile) and automotive white paint fragments for forensic examination. The technique allowed analysis of K lines of 9 trace elements in 18 titanium dioxide pigments (rutile), and 10 trace elements in finish coat layers of seven automotive white paint fragments. High‐field strength elements (HFSE) were found to strongly reflect the origin of the titanium dioxide (TiO₂) pigments, and could be used as effective parameters for discrimination and classification of the pigments and paint fragments. A pairwise comparison of the finish coat layers of seven automotive white paint fragments was performed. The trace elements in the finish coat layers detected by the high‐energy SR‐XRF were especially effective for identification. By introducing the trace element information of primer and electrocoat layers, all the automotive white paint fragments could be discriminated by this technique.     

Elemental analysis of soil samples for forensic purposes by inductively coupled plasma spectrometry--precision considerations

Major and trace elemental composition provides a powerful basis for forensic comparison of soils, sediments and rocks. However, it is important that the potential 'errors' associated with the procedures are fully understood and quantified, and that standard protocols are applied for sample preparation and analysis. This paper describes such a standard procedure and reports results both for instrumental measurement precision (repeatability) and overall 'method' precision (reproducibility). Results obtained both for certified reference materials and example soils show that the instrumental measurement precision (defined by the coefficient of variation, CV) for most elements is better than 2-3%. When different solutions were prepared from the same sample powder, and from different sub-sample powders prepared from the same parent sample, the CV increased to c. 5-6% for many elements. The largest variation was found in results for certified reference materials generated from 23 instrument runs over an 18 month period (mean CV=c. 11%). Some elements were more variable than others. W was found to be the most variable and the elements V, Cr, Co, Cu, Ni and Pb also showed higher than average variability. SiO2, CaO, Al2O3 and Fe2O3, Rb, Sr, La, Ce, Nd and Sm generally showed lower than average variability, and therefore provided the most reliable basis for inter-sample comparison. It is recommended that, whenever possible, samples relating to the same investigation should be analysed in the same sample run, or at least sequential runs.