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1.
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.  相似文献   

2.
The study was carried out to investigate external contamination of hair by blood in heroin-related post-mortem cases. Solutions were prepared containing 0.05, 0.1, 0.2, 0.5 and 3.0μg/mL of 6-monoacetylmorphine (6-AM) only or morphine only in human blood. Samples of approximately 3.2g of drug-free hair were contaminated by soaking in the blood solutions for 5min. They were then removed and left at room temperature. Approximately 0.5g of hair was collected from each of the blood soaked hair samples at 6h, 1, 2, 4 and 7 days after contamination. As each hair sample was collected it was shampoo-washed to prevent further drug absorption. Hair samples were analysed in triplicate using a fully validated method described previously. 6-AM broke down to morphine in all samples. In hair contaminated with blood containing 0.05, 0.1 and 0.2μg/mL 6-AM or morphine drug was either not detected or was detected below the limit of quantitation (0.2ng/mg hair) at all contamination times. In hair contaminated with blood spiked with 0.5μg/mL morphine, the concentration in hair ranged from 0.54 to 0.91ng/mg and in hair contaminated with blood spiked with 3.0μg/mL, from 3.25 to 5.77ng/mg. The concentrations of 6-AM ranged from 0.65 to 1.11ng/mg and morphine from 0.34 to 0.80ng/mg in hair contaminated with 0.5μg/mL 6-AM in blood. 6-AM ranged from 2.12 to 3.67ng/mg and morphine from 0.84 to 2.05ng/mg in hair contaminated with 3μg/mL 6-AM in blood. For 6-AM and morphine ANOVA statistical evaluation showed no significant difference among the concentrations over time.  相似文献   

3.
In post-mortem work, blood is a potential source of external contamination of hair. The present study was carried out to investigate the amount of drug absorbed into hair which has been contaminated with blood containing either cocaine or BE. Solutions were prepared containing 0.05, 0.1, 0.2, 0.5 and 3.0 μg/mL of either cocaine or BE in human blood. Samples of approximately 3.2 g of drug-free hair were contaminated by soaking in the blood solutions for 5 min. They were then removed and left at room temperature. Approximately 0.5 g of hair was collected from each of the blood soaked hair samples at 6 h, 1, 2, 4 and 7 days after contamination. As each hair sample was collected it was shampoo-washed to prevent further drug absorption. Hair samples were analysed in triplicate using a fully validated method described previously. EME and cocaethylene were also measured in order to find out if cocaine or BE was breaking down to these compounds. Both cocaine and BE were absorbed into hair in significant concentrations when the concentration in the blood was 0.5 μg/mL or greater; cocaine was more readily absorbed than BE. Cocaine broke down to EME (<LOQ) at 0.5 μg/mL and to EME (>LOQ) and BE (<LOQ) at 3.0 μg/mL. When the blood concentration of cocaine was 0.5 μg/mL or less, there was no evidence of it breaking down to form BE. From the samples soaked in blood containing BE, there was no evidence of the BE breaking down. The absorption of drug into hair did not increase as the contamination period increased from 6 h to 7 days.  相似文献   

4.
《Science & justice》2014,54(6):421-426
The confirmation of Δ9-tetrahydrocannabinol (THC) in oral fluid (OF) is an important issue for assessing Driving Under the Influence of Drugs (DUID). The aim of this research was to develop a highly sensitive method with minimal sample pre-treatment suitable for the analysis of small OF volumes (100 μL) for the confirmation of cannabinoids in DUID cases. Two methods were compared for the confirmation of THC in residual OF samples, obtained from a preliminary on-site screening with commercial devices. An ultra high performance LC–MS (UHPLC–MS/MS) method and an SPME–GC/MS method were hence developed. 100 μL of the residual mixture OF/preservative buffer or neat OF was simply added to 10 μL of THC-D3 (1 μg/mL) and submitted to the two different analyses: A — direct injection of 10 μL in UHPLC–MS/MS in positive electrospray ionisation (ESI) mode and B — sampling for 30 min with SPME (100 μm polydimethylsiloxane or PDMS fibre) and direct injection by desorption of the fibre in the GC injection port.The lowest limit of detection (LLOD) of THC was 2 ng/mL in UHPLC–MS/MS and 0.5 ng/mL in SPME–GC/MS. In addition, cannabidiol (CBD) and cannabinol (CBN) could be detected in GC/MS equipment at 2 ng/mL, whilst in UHPLC–MS/MS the LLOD was 20 ng/mL.Both methods were applied to 70 samples coming from roadside tests. By SPME–GC/MS analysis, THC was confirmed in 42 samples, whilst CBD was detected in 21 of them, along with CBN in 14 samples. THC concentrations ranged from traces below the lowest limit of quantification or LLOQ (2 ng/mL) up to 690 ng/mL.  相似文献   

5.
Concentrations of unconjugated morphine, codeine and 6-acetylmorphine (6-AM), the specific metabolite of heroin, were determined in urine specimens from 339 individuals apprehended for driving under the influence of drugs (DUID) in Sweden. After an initial screening analysis by immunoassay for 5-classes of abused drugs (opiates, cannabinoids, amphetamine analogs, cocaine metabolite and benzodiazepines), all positive specimens were verified by more specific methods. Opiates and other illicit drugs were analyzed by isotope-dilution gas chromatography-mass spectrometry (GC-MS). The limits of quantitation for morphine, codeine and 6-AM in urine were 20 ng/mL. Calibration plots included an upper concentration limit of 1000 ng/mL for each opiate. We identified the heroin metabolite 6-AM in 212 urine specimens (62%) at concentrations ranging from 20 ng/mL to > 1000 ng/mL. The concentration of 6-AM exceeded 1000 ng/mL in 79 cases (37%) and 31 cases (15%) were between 20 and 99 ng/mL. When 6-AM was present in urine the concentration of morphine was above 1000 ng/mL in 196 cases (92%). The concentrations of codeine in these same urine specimens were more evenly distributed with 35% being above 1000 ng/mL and 21% below 100 ng/mL. These results give a clear picture of the concentrations of unconjugated morphine, codeine and 6-acetylmorphine that can be expected in opiate-positive urine specimens from individuals apprehended for DUID after taking heroin.  相似文献   

6.
The objective of this project was to investigate the incidence of alcohol consumption in fatal traffic deaths in Shanghai, one of the largest cities in China. A study was conducted on 803 individuals killed in road accidents during the period 2009–2011, in terms of alcohol-positive rate, mean blood alcohol content (BAC), gender, age, vehicle type, pedestrian alcohol problem, single-vehicle vs multiple-vehicle crashes, and time of day. It was found that 28.9% of the drivers involved had a BAC  0.20 mg/mL (limit of civil offense) and 21.8% had a BAC  0.80 mg/mL (limit of criminal offense). The mean BAC of alcohol-positive drivers (with a BAC  0.20 mg/mL) was 1.51 mg/mL. The vast majority of the drivers involved were males. With regards to age, the largest group was of drivers aged between 40 and 49 years group in both alcohol-negative cases (26.8%) and alcohol-positive cases (26.2%). Motorcycles were most likely to be involved, representing 34.4% of alcohol-negative crashes and 51.6% of alcohol-positive crashes. Very high BACs were common among alcohol-positive pedestrians, yet all female pedestrians were alcohol-negative. Single-vehicle crashes were over-represented in alcohol-positive cases. Alcohol-negative crashes and alcohol-positive crashes most often happened during the time period of 17:00–18:59 and 19:00–20:59, respectively.  相似文献   

7.
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.  相似文献   

8.
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.  相似文献   

9.
IntroductionIn this paper, the authors presented a case of acrylamide poisoning in a middle-aged woman who had underwent unsuccessful cosmetic surgery six years earlier. The victim was told that the product that had been injected into her face was Restylane®, which mainly contained sodium hyaluronate and was the first and only Food and Drug Administration (FDA)-approved dermal filler for lip enhancement in the USA for more than 20 years. Widespread facial infections occurred several years post-injection; finally, the victim had to undergo removal surgery. Acrylamide poisoning was strongly suspected based on the victim's clinical manifestation. The product that had been injected into the victim's face was probably polyacrylamide hydrogel-based product, which had been prohibited by the State Food and Drug Administration (SFDA) in China in 2006. To confirm this suspicion, a systematical method was established to differentiate varieties of cosmetic surgery products and identify residential acrylamide.MethodsThe removed objects, original products and a certified reference sample of Restylane® were collected for examination. A direct microscopic examination was applied as a rapid screening method. Fourier transform infrared (FTIR) microspectroscopy analysis was subsequently performed to distinguish the main components from each sample. Automated solid phase extraction, ultra high performance liquid chromatography (SPE UHPLC) analysis was ultimately utilised and optimised to detect the residual acrylamide. Chromatographic separation was achieved on an ACQUITY UHPLC HSS T3 column. The mobile phase consisted of 0.01% aqueous formic acid solution and acetonitrile. The tunable UV (TUV) detection wavelength was at 202 nm.ResultsThe microscopic examination indicated that different samples had different morphological characteristics, depending on their main components. The FTIR spectrum showed that different polymers could be distinguished according to the CO stretching vibration (1655 cm? 1), NH bending vibration (1540 cm? 1) and CO stretching vibration (1078 and 1045 cm? 1). The UHPLC results demonstrated that the calibration curve was linear in the range of 0.5–20.0 μg/mL, with a correlation coefficient of 0.999. The average recoveries of the method were 99–107% with an RSD of 1.6–6.3%. The detection limit was 0.1 μg/mL (S/N = 3). The analytical time was 6 min per sample. Acrylamide was detected in the allegedly Restylane® injection.ConclusionsThis systematical method provides a rapid, accurate and sensitive determination of polyacrylamide and residual acrylamide. The microscopic and FTIR spectroscopic examinations help to verify the existence of polyacrylamide quickly and easily. The optimised SPE UHPLC-TUV method offers a simpler and more sensitive approach to confirm the amount of acrylamide, comparing to the methods in the literature.  相似文献   

10.
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.  相似文献   

11.
To validate information on cannabis use, we investigated human hair and pubic hair for cannabinoids (THC and THC-COOH) by gas chromatography/mass spectrometry. Samples (100 mg approximately) were decontaminated with methylene chloride, then pulverized and dissolved in 1 ml 1 N NaOH for 10 min at 95 °C in the presence of 200 ng of deuterated standards. After cooling, samples were extracted by n-hexane/ethyl acetate after acidification with acetic acid. After derivatization of the dry extract by PFPA/PFP-OH, the drugs were separated on a 30-m capillary column and detected using selected-ion monitoring (m/z 377 and 459 for THC and THC-COOH, respectively). Forty-three hair samples were obtained from fatal heroin overdose cases. Among them, 35% tested positive for cannabinoids. Hair concentrations ranged from 0.26 to 2.17 ng/mg (mean, 0.74 ng/mg) and 0.07 to 0.33 ng/mg (mean, 0.16 ng/mg) of THC and THC-COOH, respectively. As is generally the case for other drugs detected in hair, metabolite concentration was always lower when compared to the parent drug concentration. In pubic hair, THC concentrations ranged from 0.34 to 3.91 ng/mg (mean, 1.35 ng/mg) and THC-COOH concentrations from 0.07 to 0.83 ng/mg (mean, 0.28 ng/mg). In most cases, the highest cannabinoid concentration was found in pubic hair, suggesting that this sample may be the more suitable for cannabis testing.  相似文献   

12.
The present paper describes a qualitative and quantitative method for the simultaneous detection of opiates, cocaine and benzoylecgonine from human hair samples. Every step of the analytical procedure was studied to find the optimized conditions. Nine different incubation systems were examined. The influence of different pH values of samples on the isolation of analytes from the incubation media by Bond Elut cartridges and the stability of the compounds of interest in the different incubation media and conditions were investigated. The extracting power of different incubation media was studied as well. The phosphate buffer 0.1 N at pH 5 was chosen as the extraction medium in an optimized procedure for simultaneous determination of opiates, cocaine and benzoylecgonine in hair samples. The method developed was validated. Recoveries were 90% for morphine (M), 81% for 6-monoacetylmorphine (6-AM), 90% for codeine (CD), 86% for cocaine (C) and 90% for benzoylecgonine (BE). Relative standard deviation for inter-day precision was better than 12%. The limits of detection resulted as 0.05 ng/mg for M and C, as 0.08 for 6-AM and as 0.2 ng/mg for BE. Forty hair samples collected from drug abusers admitted to centers for detoxification treatment were analyzed obtaining 23 positive results for opiates and/or cocaine. Twelve hair specimens longer than 10 cm were analyzed following a sectional approach. In the six positive cases, it was interesting to find that the 6-AM/M ratio generally decreased for each sample from the proximal segment to the distal segments. Moreover, the 6-AM/M ratio was generally lower than 1 in the intermediate and distal segments.  相似文献   

13.
The aim of this study was to evaluate postmortem incorporation of opiates in bone and bone marrow after diacetylmorphine (heroin) administration to mice. Mice were given acute (lethal dose of 300 mg/kg) or chronic (10 and 20 mg/kg/24 h for 20 days) intraperitoneal administration of diacetylmorphine. The two metabolites of diacetylmorphine, 6-acetylmorphine (6-AM) and morphine, were extracted from whole blood, brain, spinal cord, bone marrow and bone (after hydrolysis) using a liquid/liquid method. Quantification was performed by gas chromatography-mass spectrometry (GC/MS). Results showed that after acute administration, opiates were present in all studied tissues. Morphine concentrations appeared to be higher than those of 6-AM in blood (52.4 microg/mL versus 27.7 microg/mL, n=12), bone marrow (87.8 ng/mg versus 8.9 ng/mg, n=6) and bone (0.85 ng/mg versus 0.43 ng/mg, n=6), but 6-AM concentrations were higher than those of morphine in brain (14.0 ng/mg versus 7.4 ng/mg, n=12) and spinal cord (27.8 ng/mg versus 20.8 ng/mg, n=12). No correlation was found for both compounds between blood concentrations and either brain, spinal cord, bone or bone marrow concentrations while a significant one was found between brain and spinal cord concentrations either for morphine (r=0.89, n=12, p<0.001) or 6-AM (r=0.93, n=12, p<0.001), the concentration being higher in spinal cord than in brain. When bones were stored for 2 months, only 6-AM remained in bone marrow but not in bone. After chronic administration, mice being sacrificed by cervical dislocation 24 h after the last injection, no opiate was detected in any studied tissues. Further studies are required, in particular in human bones, but these results seem to show that 6-AM could be detect in bone marrow several weeks after the death and could be an alternative tissue for forensic toxicologist to detect a fatal diacetylmorphine overdose, even if no correlation between blood and bone marrow was observed. On the other hand, neither bone tissue nor bone marrow will allow the confirmation of a chronic diacetylmorphine use.  相似文献   

14.
Previous studies have documented gender-related differences in a number of aspects of the pharmacology of opiates, including their analgesic activity, stimulative properties and generation of physical dependence. The current experiments were carried out with the aim to examine whether male–female differences exist in the blood and brain levels of opiates attained after their intraperitoneal injection to male and female Wistar rats. The tests were performed 5, 15, 45 and 120 min after the animal treatment with seized heroin. Gas chromatography–mass spectrometry (GC–MS) method was developed to quantitatively determine opiate alkaloids in blood and brain regions (known for their high concentration of μ-opiate receptors): cortex, brainstem, amygdala and basal ganglia. Maximal contents of opiates in blood of animals of both genders were found in the second measurement time (15 min), the values measured in the males being significantly higher, which suggests a faster passage of the opiates from blood to brain tissue in female animals. The highest content of opiates in the brain tissue of female animals was measured 15 min and with male animals 45 min after the treatment, which also indicates faster distribution of opiates from blood to brain in the female compared to male rats. The highest proportion of opiates was found in the basal ganglia of the animals of both genders. The obtained results offer the possibility of selecting this part of the brain tissue of both males and females as a representative sample for identifying and assessing contents of opiates.  相似文献   

15.
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.  相似文献   

16.
目的确定海洛因吸毒者头发中海洛因、6-单乙酰吗啡(6-MAM)、吗啡(MOR)、可待因(COD)和乙酰可待因(AC)的浓度并考察其与国际毛发分析协会(Society of Hair Testing,SOHT)建议标准的适用性。方法 50个头发样品经冷冻研磨处理后采用液相色谱-串联质谱方法分析。结果所有样品中均检出6-MAM,并且浓度高于SOHT所建议的0.2 ng/mg,其中海洛因、6-MAM、MOR、COD和AC的浓度与其它研究报道无明显差异。头发中6-MAM:MOR的比率在0.15~36.27范围。结论由于各实验室间毛发样品前处理方法不同,而且存在吸食毒品中成分、剂量、吸食方式、代谢、头发颜色等诸多个体差异,本研究认为采用头发中6-MAM:MOR的比率大于1.3标准难以应用于鉴定海洛因吸毒。  相似文献   

17.
《Science & justice》2014,54(6):451-458
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.  相似文献   

18.
The quali-quantitative determination of two barbiturates, thiopental and its metabolite pentobarbital, in head and pubic hair samples of a woman who had been sexually assaulted during hospitalisation, is reported. Hair was analysed by means of solid-phase microextraction (SPME) and gas chromatography-multiple mass spectrometry (GC-MS-MS), in chemical ionisation conditions. Thiopental and pentobarbital were found in three proximal head hair segments (sample 1A: 0.30 and 0.40 ng/mg; sample 1B: 0.20 and 0.20 ng/mg; sample 3: 0.15 and 0.20 ng/mg) and pubic hair sample. Two distal head hair segments were negative for both barbiturates. Despite the lack of collection and toxicological analysis of blood or urine samples within the hospital setting, analytical findings from hair revealed the use of the anaesthetic agent thiopental to sedate the victim quickly and deeply and commit sexual assault.  相似文献   

19.
Recently, different portable hand-held and battery-powered dental X-ray units have become available. Especially for forensic odontological purposes, they offer diverse advantages such as for use in disaster areas and crime-scene locations as also in autopsy rooms and mortuaries. For any application, the most important feature of these hand-held devices is the delivered image quality. The aim of this study is to evaluate the radiographic image quality acquired by two portable X-ray devices in combination with two types of image receptors and to compare the findings with the image quality of a standard intra-oral X-ray device.Eleven samples consisting of eight teeth, two dry skeletal specimens and one formalin-fixed mandible part were mounted on blocks for standardised (re)positioning. Radiological images were acquired with two hand-held (AnyRay® 60 kVp, 0.02–4.00 mAs and NOMAD® 60 kVp, 0.023–2.277 mAs) and one wall-mounted (MinRay® 60/70 kVp 0.14–22.4 mAs) X-ray device combined with two image receptor systems (VistaScan® phosphor storage plate (PSP) and SIGMA® M CMOS Active Pixel technology sensor). The effect of X-ray source-to-object distance (SOD) was checked at 20 cm in conjunction with object to image receptor distances (OIDs) of 0.8 and 2.5 cm. For each parameter setup, the exposure times were run from low till high. An expert consent statement was achieved by agreement of four expert observers selecting the optimal images based on a developed four point quality rating system. Next, a selection of the images was assembled in a set of 198 observation screens and scored by seven observers. The observation screens were designed to compare observer scores, relations between devices, receptors and OIDs and images obtained from the different devices at equal exposure levels (mAs). All results were statistically analysed.Radiological image quality was significantly higher for phosphor plate compared with the CMOS digital receptor system (p < 0.0001). Furthermore, a significantly superior image quality was obtained for OID = 0.8 than for OID = 2.5 (p = 0.039). A significant difference in image quality between the three devices was also established (p = 0.02). The present study demonstrated the feasibility of portable X-ray systems for forensic odontological applications based on rendering optimal image quality, provided an in vitro guideline of optimal parameter settings and offered a radiological image database usable in further research.  相似文献   

20.
One of the most controversial point regarding the validity of hair testing is the risk of false positive due to external contamination. The aim of our experience is to verify if a 5 consecutive days contamination with a small amount of a powdered mixture of heroin hydrochloride and acetylcodeine hydrochloride (10:1 w/w) will last sufficiently long to make a contaminated subject indistinguishable from active users, and if normal washing practices together with the decontamination procedure are sufficient to completely remove the external contamination.Our results suggest that decontamination procedures are not sufficient to remove drugs penetrated into hair from external source. In fact, all contaminated subjects were positive for opiates (heroin, 6-MAM, morphine, acetylcodeine and codeine) for at least 3 months.Significant 6-MAM concentrations (>0.5 ng/mg) were found in each subject until 6th week. Further, 6-MAM/morphine ratio were always above 1.3.  相似文献   

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