• Journal of The Korean Society of Clinical Toxicology
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• v.15 no.2
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• pp.101-106
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• 2017

Purpose: This study examined the patterns of drugs, poisons, and chemicals detected in autopsy samples performed in the Seoul Institute and other regional forensic offices of the National Forensic Service (NFS) between 2014 and 2016. Methods: The investigation carried out using the laboratory information management system. Forensic toxicological identification and quantitation were performed in autopsy samples, including heart blood, peripheral blood, liver, kidney, vitreous humor and etc. Gas chromatography/mass spectrometry (GC-MS) and liquid chromatography-tandem mass spectrometry (LC-MS/MS) were used to analyze the drugs and poisons. Results: Forensic autopsies were performed on 9,674 cases in this period. Based on the autopsy reports, 699 cases (7.2%) were considered as unnatural deaths caused by fatal intoxication. The number of male deaths was higher than that of female deaths, with the age of 50-59 being the most common age group. Conclusion: Drugs comprised the largest number of deaths due to poison, followed by alcohol, agrochemicals, drug with alcohol, carbon monoxide, and cyanide, in that order. Zolpidem was the most frequently used drug in all drug-related intoxication cases.

• Analytical Science and Technology
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• v.34 no.3
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• pp.115-121
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• 2021

Ethyl glucuronide (EtG) and ethyl sulfate (EtS), which are ethanol metabolites, are direct indicators of ethanol intake; they have been studied in a variety of biological samples in forensic science. It is necessary to analyze ethanol metabolites to determine whether the ethanol detected in autopsy cases was due to alcohol consumption before death or due to the ethanol produced from post-mortem decay. In general, EtG and EtS are detected in the blood together with ethanol; however, it may be difficult to secure blood depending on the extent of decay. Therefore, the aforementioned method should be replaced by detecting the ethanol metabolites using tissue biological samples. In this study, we determined the optimal experimental conditions for detecting EtG and EtS from spleen samples using Liquid Chromatography - Tandem Mass Spectrometry (LC-MS/MS). Herein, the test method was validated, and an analysis method was applied to the actual autopsy cases.

• Applied Chemistry for Engineering
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• v.28 no.4
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• pp.490-494
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• 2017

With increasing the number of vehicles, the accident rate also goes up and the damaged vehicles should be painted as a final repair process. At the painting stage the solvent-based paint causes environmental problems. To overcome these problems waterborne refinish paint is frequently used recently. However, for waterborne refinish, the costs of insurance coverage are too expensive, and insurance reimbursement costs could be burdensome. Because of the high price of aquatic paint treatment, the service shop might charge the malicious service price. In this study, the surfactant of Surfynol 104, which is the component in the paint, was used as an indicator whether the vehicle was painted with waterborne paint. The specimen was quantitatively analyzed to contain 0.38% of the surfactant through the standard addition method with isotope substituted internal standard (IS) of fluranthene-d10 by curie point pyrolysis-gas chromatography/mass spectrometry (Py-GC/MS).

• Analytical Science and Technology
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• v.36 no.4
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• pp.170-179
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• 2023

Starvation, diabetes, alcoholism and hypothermia cause ketoacidosis in the human body; therefore, the cause of death can be determined by analyzing ketone bodies in the blood of the deceased. In the case of decomposition of the cadaver, however, since collecting intact blood is impossible, ketone body analysis is performed using the spleen. However, the index for diagnosing ketoacidosis is based on blood concentration, and its correlation with ketone bodies present in the spleen remains unknown. In particular, since decomposition proceeds rapidly during summer, when temperature and humidity are high, understanding the correlation between ketone bodies in the blood and spleen is important to estimate the state at the time of death from a decaying body. Therefore, in the present study, the correlation between ketone bodies in the blood and spleen of the deceased was explored. Ketone bodies (beta-hydroxybutyric acid [BHB] and acetone) in the blood and spleen were analyzed and compared from autopsies (>100 mg·L^-1 BHB, blood basis) conducted at the Daejeon Forensic Research Institute from June to December 2021. Moreover, the concentration of ketone bodies in the spleen juice and tissues was compared assuming the scenario of extreme decomposition. Ketone retention concentration in the blood and spleen was positively correlated, and the ratio of BHB concentration in the spleen to BHB concentration in the blood ranged from 0.52 to 1.08 (mean = 0.85 ± 0.12), although the ratio may vary depending on the degree of decomposition of the corpse.

• Bulletin of the Korean Chemical Society
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• v.33 no.12
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• pp.4243-4246
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• 2012

• Bulletin of the Korean Chemical Society
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• v.34 no.8
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• pp.2413-2418
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• 2013

Forensic and legal medicine require reliable data to indicate excessive alcohol consumption. Ethanol is oxidatively metabolized to acetate by alcohol dehydrogenase and non-oxidatively metabolized to ethyl glucuronide (EtG), ethyl sulfate (EtS), phosphatidylethanol, or fatty acid ethyl esters (FAEE). Oxidative metabolism is too rapid to provide biomarkers for the detection of ethanol ingestion. However, the non-oxidative metabolite EtG is a useful biomarker because it is stable, non-volatile, water soluble, highly sensitive, and is detected in body fluid, hair, and tissues. EtG analysis methods such as mass spectroscopy, chromatography, or enzyme-linked immunosorbent assay techniques are currently in use. We suggest that nuclear magnetic resonance (NMR) spectroscopy could be used to monitor ethanol intake. As with current conventional methods, NMR spectroscopy doesn't require complicated pretreatments or sample separation. This method has the advantages of short acquisition time, simple sample preparation, reproducibility, and accuracy. In addition, all proton-containing compounds can be detected. In this study, we performed $^1H$ NMR analyses of urine to monitor the ethanol and EtG. Urinary samples were collected over time from 5 male volunteers. We confirmed that ethanol and EtG signals could be detected with NMR spectroscopy. Ethanol signals increased immediately upon alcohol intake, but decreased sharply over time. In contrast, EtG signal increased and reached a maximum about 9 h later, after which the EtG signal decreased gradually and remained detectable after 20-25 h. Based on these results, we suggest that $^1H$ NMR spectroscopy may be used to identify ethanol non-oxidative metabolites without the need for sample pretreatment.

• Applied Chemistry for Engineering
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• v.29 no.3
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• pp.356-361
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• 2018

It is common to analyze volatile organic compound (VOC) or semi-VOC (SVOC) in a sample composed of a complex matrix consisting of multiple components such as bloods through a separation process. Adsorption is a physical phenomenon in which certain components accumulate on the surface of other phases. In order to overcome difficulties in the pretreatment process, an adsorption is frequently used. Solid phase microextraction (SPME) equipment with porous carbon carboxen (CAR) is an example of adsorption application. In this study, the adsorption of 4-octylphenol to carboxen was examined. To do so, the extraction efficiency for such solvents as dichloromethane ($CH_2Cl_2$, DCM), ethylacetate ($CH_3COOC_2H_5$, EA) and diethylether ($C_2H_5OC_2H_5$, $Et_2O$) was studied and also the derivatization reaction for 4-octylphenol with reagents of bistrimethylsilyltrifluoroacetamide (BSTFA), methylchloroformate (MCF) and pentafluorobenzylbromide (PFBBr) was compared. The combination of DCM and BSTFA showed good performance thus they were adopted for this study. Thermodynamic adsorption experiments showed that the adsorption process was endothermic and Freundlich isotherm equation was more suitable than Langmuir isotherm. It was also found that the adsorption followed a pseudo-$2^{nd}$ order kinetic model.

• Analytical Science and Technology
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• v.36 no.2
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• pp.80-88
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• 2023

Fingerprints play a crucial role in the identification of potential suspects in criminal cases. However, determining the actual time, i.e., the time at which the fingermark was deposited, is challenging. Herein, we investigated the persistence and aging of fingerprints over time by observing the time evolution of latent fingerprints on a polystyrene box stored in a dark room. Fingerprint samples that were stored for up to two years could be detected with maximum accuracy using a black iron-oxide-based emulsion (black emulsion). To estimate the time of fingerprint deposition, fingerprint aging was studied by analyzing the lipid components of the fingerprints after their development. Cholesterol and squalene were selected as indicators of fingerprint aging, and their ratio was estimated to assess aging. In the case of fingerprint samples stored in a dark room for up to one month after deposition, the cholesterol/squalene ratio was approximately 0.01; it increased gradually to ≥ 0.1 over six months. A substantial reduction in the levels of cholesterol and squalene from the initial levels was also noted. Cholesterol and squalene were not detected after one year of storage. Thus, the extent of aging could be determined by analyzing the aging indicators for up to six months. Two cases that could cause error in the estimation of the fingerprint deposition time, namely, heating of the fingerprint sample before development and storage of the developed fingerprints in a dark room, were also investigated.

• Analytical Science and Technology
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• v.29 no.2
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• pp.73-78
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• 2016

Hydrogen cyanide (HCN) is an extremely toxic gas frequently produced during the incineration of plastics, such as acrylonitrile-butadiene-styrene (ABS). A victim of a fire who has inhaled smoke could have cyanide in the blood. Therefore, cyanide could be a good marker for a post-mortem examination of a fire as well as carboxyhemoglobine (COHb) test of blood samples. For a particular fire case, a burned body with a suicide note was found inside a burned vehicle. Even though the COHb value is conclusive evidence, measuring the COHb for denatured blood might be difficult due to severe thermal denaturation or the formation of methemoglobin (MetHb). To overcome this difficulty, cyanide could be used as an indicator when investigating the death of a fire victim. In this study, gas chromatography/mass spectrometry (GC/MS) was adopted to measure the levels of cyanide in the blood through derivatization with pentafluorobenzyl bromide (PFBBr) under cation surfactant by scan and SIM mode. The concentration of cyanide in the blood of heart blood and brain of the victim was found to be 0.36 µg/mL and 1.20 µg/mL respectively, which was higher than the average value (0.041 µg/mL) found in the blood of 14 people who smoked.

• Analytical Science and Technology
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• v.33 no.2
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• pp.98-107
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• 2020

Methamphetamine (MA) is currently the most abused illicit drug in Korea. MA is produced by chemical synthesis, and the final target drug that is produced contains small amounts of the precursor chemicals, intermediates, and by-products. To identify and quantify these trace compounds in MA seizures, a practical and feasible approach for conducting chromatographic fingerprinting with a suite of traditional chemometric methods and recently introduced machine learning approaches was examined. This was achieved using gas chromatography (GC) coupled with a flame ionization detector (FID) and mass spectrometry (MS). Following appropriate examination of all the peaks in 71 samples, 166 impurities were selected as the characteristic components. Unsupervised (principal component analysis (PCA), hierarchical cluster analysis (HCA), and K-means clustering) and supervised (partial least squares-discriminant analysis (PLS-DA), orthogonal partial least squares-discriminant analysis (OPLS-DA), support vector machines (SVM), and deep neural network (DNN) with Keras) chemometric techniques were employed for classifying the 71 MA seizures. The results of the PCA, HCA, K-means clustering, PLS-DA, OPLS-DA, SVM, and DNN methods for quality evaluation were in good agreement. However, the tested MA seizures possessed distinct features, such as chirality, cutting agents, and boiling points. The study indicated that the established qualitative and semi-quantitative methods will be practical and useful analytical tools for characterizing trace compounds in illicit MA seizures. Moreover, they will provide a statistical basis for identifying the synthesis route, sources of supply, trafficking routes, and connections between seizures, which will support drug law enforcement agencies in their effort to eliminate organized MA crime.