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.     

浙江省三门县沿海地区人群血液和尿液中33种元素的生物监测(英文)

目的确立华东典型沿海地区浙江省三门县一般人群血液和尿液中33种元素(Ag、Al、As、Au、B、Ba、Be、Ca、Cd、Co、Cr、Cs、Cu、Fe、Ga、Hg、Li、Mg、Mn、Mo、Ni、Pb、Rb、Sb、Se、Sr、Th、Ti、Tl、U、V、Zn和Zr)的正常值参考范围。方法采用电感耦合等离子体质谱法检测272例血液样本和300例尿液样本中33种元素。采用SPSS 17.0软件对所得数据进行正态性检验,将所得数据与已有文献报道进行对比。结果建立了三门县一般人群血液和尿液中33种元素的正常值参考范围,其中Co、Cu、Mn和Sr等元素的正常值参考范围与其他报道相似,而As、Cd、Hg和Pb与其他研究报道存在差异,一般为高于其他报道,而血液中的Ba元素在各国文献报道之间差异较大。结论建立了三门县人群血液和尿液中33种元素的正常值参考范围,并成功应用于两例中毒案例的检测。     

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.     

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.     

Lead-free primer residues: a qualitative characterization of Winchester WinClean, Remington/UMC LeadLess, Federal BallistiClean, and Speer Lawman CleanFire handgun ammunition

The elemental composition and postfiring residues of several "lead-free" or "nontoxic" centerfire handgun ammunition types currently available to the general public were examined. Offerings from Winchester, Remington/UMC, Federal and Speer were obtained from retail sources in both .45 ACP and 9 mm when possible. A total of 112 postfiring residue samples (SEM pins) were collected at varying distances from the muzzle, at two distances from target and from the shooter's hands. An additional 20 samples were collected by direct ignition of primers. Qualitative determinations were carried out using scanning electron microscopy (SEM)/electron dispersive spectrometry (EDS) analysis. All types tested contained aluminum (Al), silicon (Si), copper (Cu), and zinc (Zn). Most contain traces of sulfur and calcium. Winchester WinClean and Remington LeadLess contained potassium as the principle ingredient. Federal BallistClean contained barium, while Speer Lawman CleanFire contained strontium. In the main, these compared favorably with manufacturers' MSDS publications and patents granted. The characterizations undertaken here will be of use to the forensic electron microscopist as these formulations gain popularity.     

Determination of Trace Elemental Concentrations in Document Papers for Forensic Comparison Using Inductively Coupled Plasma–Mass Spectrometry

Abstract:  With improvements in manufacturing procedures, comparing physical characteristics of paper samples may not offer sufficient discrimination among different vendors. In this work, the potential to differentiate paper samples based on trace element concentrations was investigated. Paper samples from two different vendors were microwave-digested and trace element concentrations (Mg, Al, Mn, Fe, Sr, Y, Ba, Ce, and Nd) were determined using inductively coupled plasma–mass spectrometry. Differences in concentration were assessed statistically using two-way ANOVA and Tukey's honestly significant differences test. Elemental concentrations were shown to be consistent across a single sheet as well as within a single ream of paper for each vendor. Reams from vendor A were differentiated based on Al and Ba concentration while reams from vendor B were differentiated based on Mg, Mn, and Sr concentrations. Paper was differentiated according to vendor based on significant differences in Ba, Sr, Ce, and Nd concentrations.     

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.     

Measurement of airborne gunshot particles in a ballistics laboratory by sector field inductively coupled plasma mass spectrometry

The present study aimed determines lead (Pb), antimony (Sb) and barium (Ba) as the major elements present in GSR in the environmental air of the Ballistics Laboratory of the S?o Paulo Criminalistics Institute (I.C.-S.P.), S?o Paulo, SP, Brazil. Micro environmental monitors (mini samplers) were located at selected places. The PM(2.5) fraction of this airborne was collected in, previously weighted filters, and analyzed by sector field inductively coupled plasma mass spectrometer (SF-HR-ICP-MS). The higher values of the airborne lead, antimony and barium, were found at the firing range (lead (Pb): 58.9 μg/m(3); barium (Ba): 6.9 μg/m(3); antimony (Sb): 7.3 μg/m(3)). The mean value of the airborne in this room during 6 monitored days was Pb: 23.1 μg/m(3); Ba: 2.2 μg/m(3); Sb: 1.5 μg/m(3). In the water tank room, the air did not show levels above the limits of concern. In general the airborne lead changed from day to day, but the barium and antimony remained constant. Despite of that, the obtained values suggest that the workers may be exposed to airborne lead concentration that can result in an unhealthy environment and could increase the risk of chronic intoxication.     

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。     

Primer residue analysis of ammunition of Indian origin by neutron activation analysis

The primer residues of ammunition manufactured in India have been analysed by neutron activation analysis (NAA). Since NAA is rather insensitive for lead, attention was confined to the elements antimony, barium, copper and mercury. The element/element combinations detected in significant amounts were (Sb), (Ba, Hg), (Ba, Cu, Sb), (Cu, Hg, Sb) and (Hg, Sb). The present study reveals the presence of Hg from mercury fulminate in priming compositions long discontinued in most ammunition of foreign origin. The presence of Hg can be advantageous in certain situations where the matrix on which the residue is deposited contains high levels of antimony such as clothing made of synthetic fibres. Caution is also required in interpreting the Cu values as being solely due to a jacketed projectile.     

Detection of Pb,Ba, and Sb in Cadaveric Maggots and Pupae by ICP-MS*

The concentrations of lead (Pb), barium (Ba), and antimony (Sb), characteristic of GSR, were determined in soil sediments and immature (larvae) of cadaveric flies of the family Calliphoridae, by inductively coupled plasma mass spectrometry (ICP-MS). This research refers to a case study from two real crime scenes in which the corpses were in an advanced state of decomposition. In case 1, the victim had holes similar to gunshot wounds, and in case 2, there was no evidence of perforations in the corpse. Soil sediment collection was performed at three different points of the terrain, at a minimum distance of 10 m from the corpse, for cases 1 and 2. In relation to the collection of immatures, larvae were collected in regions of the mouth, nose, and orifices similar to the entry of firearms projectile into the body, for case 1, and collection of larvae and pupae, located on the body and underneath it, for case 2. It was possible to detect and quantify the three elements of interest (Pb, Ba, and Sb) by ICP-MS in both sediment and cadaveric larvae. Concentrations of 4.44, 8.74, and 0.08 μg/g were obtained for Pb, Ba, and Sb, respectively, in the soil for case 1. For the case 2, the concentrations in Pb, Ba, and Sb were from 16.34 to 26.02 μg/g; from 32.64 to 57.97 μg/g and from 0.042 to 0.30 μg/g, respectively. In the larvae, Pb, Ba, and Sb were quantified in cases 1 and 2 with a concentration of 6.28 and 1.78 μg/g for Pb, 1.49 and 2.94 μg/g for Ba, 0.50 μg/g and <LD for Sb, respectively. These new results present the detection of characteristic elements of GSR in cadaveric larvae in humans in a real crime scene, besides highlighting the importance of the study of immature flies, using the ICP-MS technique in forensic analysis.     

Experimental designs in the optimisation of ultrasonic bath-acid-leaching procedures for the determination of trace elements in human hair samples by atomic absorption spectrometry

Experimental designs were used for the optimisation of acid-leaching procedures assisted by ultrasonic energy for the extraction of Ca, Cu, Fe, Mg, Mn and Zn from human hair samples. A Plackett-Burman 2(7) x 3/32 design for seven factors ([HNO3], [HCl], [H2O2], acid/oxidant solution volume, exposure time to ultrasounds, temperature of the ultrasonic bath and hair particle size) was used in order to choose the variables affecting the acid-leaching process. The variables [HNO3], [HCl] and temperature of the ultrasonic bath were found to be the most important parameters for the acid-leaching procedure, and these variables were optimised by a response surface design (central composite design 2(3) + star) which involved 16 experiments. Optimum values in the 3.7-4.2 M range were found for [HNO3], while optimum values between 3.0 and 3.5 M were found for [HCl]. The optimum temperature of the ultrasonic bath was between 80 and 90 degrees C. An acid digestion induced by microwave energy (details given) was used to obtain the total metal concentration and also for comparative purposes. Ca, Cu, Fe, Mg and Zn were measured by flame atomic absorption spectrometry (FAAS) using a conventional air/acetylene flame, while Mn was determined by electrothermal atomic absorption spectrometry (ETAAS) under optimised conditions. Two different reference materials, IAEA-085 International Atomic Energy Agency, Monaco) and NIES No. 13 (National Institute for Environmental Studies, Japan), with certified metal contents for some of the elements investigated, were used in order to verify the accuracy of the methods.     

A fast ultrasound-assisted extraction procedure for trace elements determination in hair samples by ICP-MS for forensic analysis

An ultrasound-assisted extraction method is proposed for the determination of trace elements in hair samples by inductively coupled plasma-mass spectrometry (ICP-MS) for forensic investigation. Prior to analysis, 25 mg of hair samples were accurately weighed into (15 mL) conical tubes. Then, 2 mL of 20% HNO₃ is added to the samples, sonicated at 2 min (50 W, 100% amplitude), and then further diluted to 10 mL with Milli-Q water. Resulted diluted slurries are centrifuged and the analytes are directly determined in the supernatant. Calibrations against aqueous solutions were carried out with rhodium as internal standard. The method was successfully applied for the extraction of Al, As, Ba, Be, Cd, Co, Cr, Cu, Mn, Pb, Tl, U, V and Zn with a method detection limit (3 s, n = 20) of 0.1, 0.4, 0.2, 0.09, 0.08, 0.04, 0.1, 2.9, 1.0, 0.9, 0.04, 0.05, 0.1 and 4.2 ng/g, respectively. Method accuracy is traceable to Certified Reference Materials (CRMs) 85 and 86 human hair from the International Atomic Energy Agency (IAEA). Additional validation data are provided based on the analysis of hair samples from the trace elements intercomparison program operated by the Institut National de Sante’ Publique du Quebec, Canada. The proposed method is very simple and can be applied for forensic purposes with the elimination of sample digestion step prior to analysis. Then, a considerable improvement in the sample throughput is archived with the use of the proposed method.     

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

Chemical and physicochemical examinations of the fragments of an Egyptian mummy dated between the 3rd and 1st century B.C. were performed. The chemical examinations indicated the presence of resin in the skull and in the fragments of bandages wrapped around the mummy. An analysis of the infrared spectra of the fragments indicated a type of resin originating from the Copal group. Physicochemical investigations showed that main chemical elements such as Ca, Mg, Na, K, P and trace chemical elements such as Fe, Zn, Cu, and Pb occurred in bone fragments in proportions typical for people living today. In tooth fragments, values were similar to normal except for K, P, and Zn, which were lower, and Pb, which was absent. In the fingernails, most elements were found in much higher concentrations except for Cu and Pb, which were lower. The results of the study in terms of their implications on mummification are discussed.     

Determination of heavy metals in some human organs, tissue, and fluids under normal conditions

A table has been created, presenting normal levels of heavy metals (Hg, Cd, Cr, Cu, Fe, Mn, Pb, Ni, Zn, Sn, Tl, Ag) in human biological media. In contrast to other handbooks, the authors use the normal values derived on the basis of their own investigations at the spectral laboratory of Bureau of Forensic Medical Expert Evaluations, Public Health Committee of Moscow and published reports. Comparative analysis was carried out for each element in human organs, tissues, and urine, which will facilitate expert work. Every laboratory engaged in expert evaluations and analysis in cases with suspected poisoning with heavy metal salts is to have reference values of these elements' concentrations in human organs and tissues obtained in this very laboratory on available equipment with consideration for specific features of its biogeochemical region.     

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.     

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。     

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.     

微波消解ICP-MS法测定人头发中24种元素的含量

目的建立人头发中24种无机元素的电感耦合等离子体质谱（inductively coupled plasma-mass spec-trometry,ICP-MS）分析方法。方法采用微波消解法处理样品,以铟（115In）作内标,用ICP-MS分析人头发中的24种元素含量。同时检测56例健康志愿者和10例海洛因滥用者头发中24种元素含量。结果 24种元素的方法检出限范围为0.0003~10.14μg/g,标准物质的测得值与标准值基本相符。海洛因滥用者经戒毒治疗后头发中镁、镓、钡含量下降。结论该方法灵敏度、准确度高,适用于头发中24种元素的测定。