{"title":"Postmortem distribution of thiamethoxam in biological fluids and solid tissues measured through liquid chromatography-tandem mass spectrometry using the standard addition method.","authors":"Kazumichi Kakazu, Kenji Ninomiya, Chiaki Fuke, Natsuki Ikematsu, Maki Fukasawa, Mio Takayama","doi":"10.1007/s11419-026-00765-4","DOIUrl":"10.1007/s11419-026-00765-4","url":null,"abstract":"<p><p>PURPOSE: To our knowledge, no previous reports have described the postmortem distribution of thiamethoxam in fatal cases. This study aimed to quantify thiamethoxam in biological fluids and solid tissues from a suicide involving ingestion of Actara® insecticide (10% thiamethoxam) using liquid chromatography–tandem mass spectrometry (LC–MS/MS). METHODS: Biological fluids and solid tissue homogenates were deproteinized with methanol. Thiamethoxam-d4 served as the internal standard. The standard addition method was used for quantification. RESULTS: Thiamethoxam was detected in all analyzed specimens, including 4 biological fluids, 11 solid tissues, and stomach contents. Thiamethoxam concentrations in each specimen, excluding the stomach contents, ranged from 2.5 to 53.6 µg/mL(g). The correlation coefficients (r2) for the calibration curves ranged from 0.9934 to 0.9996. Intraday and interday variability were < 8.9% and < 11.1%, respectively. CONCLUSIONS: Thiamethoxam was quantified in biological fluids and solid tissues obtained at autopsy using LC–MS/MS with standard addition. To our knowledge, this is the first detailed report on the postmortem distribution of thiamethoxam.</p>","PeriodicalId":12329,"journal":{"name":"Forensic Toxicology","volume":" ","pages":"356-362"},"PeriodicalIF":2.1,"publicationDate":"2026-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147510932","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Characterization of fluvoxamine degradation products in postmortem blood by liquid chromatography coupled with quadrupole-Orbitrap mass spectrometry.","authors":"Yoshikazu Yamagishi, Kazuaki Takahashi, Hiroyuki Inoue, Sayaka Nagasawa, Hirotaro Iwase, Yasumitsu Ogra","doi":"10.1007/s11419-026-00763-6","DOIUrl":"10.1007/s11419-026-00763-6","url":null,"abstract":"<p><p>PURPOSE: Fluvoxamine (FLV) is a selective serotonin reuptake inhibitor primarily used to treat obsessive-compulsive disorder. In Japan, FLV is linked to lethal intoxication and suicide cases. Therefore, it is important to establish its exact concentration in postmortem (PM) blood. It has been reported that blood FLV concentration decreases over time. In this study, we aimed to clarify the mechanisms underlying changes in FLV concentration in human blood over time. METHODS: We examined whether FLV underwent hydroxylation and/or oxidation in a Fenton reaction mixture containing FeCl2, hemoglobin (Hb), or hydrogen peroxide (H2O2) after incubating at 37 °C for 24 h. In addition, we measured FLV and its degradation products in human blood by liquid chromatography coupled with quadrupole-Orbitrap mass spectrometry. RESULTS: Mass spectrometric result indicated the formation of (E)-N-(2-(((5-methoxy-1-(4(trifluoromethyl)phenyl)pentylidene)amino)oxy)ethyl)formamide (FLV-CHO), (E)-5-hydroxy-1-(4-(trifluoromethyl)phenyl)pentan-1-one-O-(2-aminoethyl)oxime (FLD), and (E)-5-(hydroxymethoxy)-1-(4-(trifluoromethyl)phenyl)pentan-1-one-O-(2-aminoethyl)-oxime (FLV-OH) in the reaction mixture. In addition, FLV-CHO concentration in human blood was strongly correlated with percentage FLV degradation relative to its initial concentration. CONCLUSIONS: Our results indicate that FLV-CHO, formed by Hb/H2O2-mediated FLV degradation in blood, is a potential biomarker for correcting FLV concentration in PM blood.</p>","PeriodicalId":12329,"journal":{"name":"Forensic Toxicology","volume":" ","pages":"349-355"},"PeriodicalIF":2.1,"publicationDate":"2026-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC13303306/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147467319","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Forensic ToxicologyPub Date : 2026-07-01Epub Date: 2026-01-19DOI: 10.1007/s11419-026-00756-5
M Vijayasimha
{"title":"From field prick to decision-grade proof: a dried blood spot and volumetric absorptive microsampling framework for verifying chemical-agent exposure.","authors":"M Vijayasimha","doi":"10.1007/s11419-026-00756-5","DOIUrl":"10.1007/s11419-026-00756-5","url":null,"abstract":"","PeriodicalId":12329,"journal":{"name":"Forensic Toxicology","volume":" ","pages":"458-460"},"PeriodicalIF":2.1,"publicationDate":"2026-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145997694","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Forensic ToxicologyPub Date : 2026-07-01Epub Date: 2026-06-06DOI: 10.1007/s11419-026-00772-5
Cristina Sempio, Jorge Campos-Palomino, Jelena Klawitter, Erica N Peters, Laura MacNair, Mehdi Haghdoost, Marcel Bonn-Miller, Amy Harrison, Shanna Babalonis, Marilyn A Huestis, Uwe Christians, Jost Klawitter
{"title":"Metabolite patterns in human urine after oral administration of highly purified Δ8-THCV.","authors":"Cristina Sempio, Jorge Campos-Palomino, Jelena Klawitter, Erica N Peters, Laura MacNair, Mehdi Haghdoost, Marcel Bonn-Miller, Amy Harrison, Shanna Babalonis, Marilyn A Huestis, Uwe Christians, Jost Klawitter","doi":"10.1007/s11419-026-00772-5","DOIUrl":"10.1007/s11419-026-00772-5","url":null,"abstract":"<p><strong>Introduction: </strong>The interest in therapeutic applications of tetrahydrocannabivarin (THCV) recently increased. For this reason, we validated an online extraction liquid chromatography- tandem mass spectrometry (LC-MS/MS) method to investigate the formation of urinary metabolites and understand potential cross-reactivity of THCV metabolites in cannabinoid immunoassays.</p><p><strong>Method: </strong>Urine samples were obtained after oral administration of Δ8-THCV to healthy participants. The protocol was approved by the Advarra Institutional Review Board (Pro00059879; approved December 20, 2021) and the trial was registered on clinicaltrials.gov (NCT05210634). Urine samples were collected pre-dose and pooled 0-8 hours post-dose. Urine samples were extracted using a simple one-step protein precipitation procedure and the extracts analyzed using online trapping LC-MS/MS in positive multiple reaction monitoring mode.</p><p><strong>Results and discussion: </strong>All compounds passed validation criteria in urine. In the clinical samples, 11-nor-9-carboxy-Δ8-THCV (Δ8-THCV-COOH) was the main metabolite detected before and after incubation with glucuronidases. Of the urine pooled 0-8 hours post-dose, 70 out of 80 were reported positive by a cannabinoid immunoassay targeting Δ9-THC-COOH, despite being negative for Δ9-THC-COOH and positive mainly for Δ8-THCV-COOH in the LC-MS/MS analysis.</p><p><strong>Conclusions: </strong>The major metabolites of Δ8-THCV in urine were Δ8-THCV-COOH, 11-hydroxy-Δ8-THCV and Δ9-THCV-COOH that were extensively glucuronidated and cross-react with immunoassay routinely used for toxicology testing resulting in false positive results for Δ9-THC exposure.</p>","PeriodicalId":12329,"journal":{"name":"Forensic Toxicology","volume":" ","pages":"437-444"},"PeriodicalIF":2.1,"publicationDate":"2026-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"148175714","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Forensic ToxicologyPub Date : 2026-07-01Epub Date: 2026-03-26DOI: 10.1007/s11419-026-00762-7
Fumiya Morioka, Atsushi Nitta, Noriaki Shima, Jun Yoshida, Kazuya Mori, Munehiro Katagi, Takako Sato
{"title":"Application of segmental hair analysis to elucidate routine and immediately pre-mortem drug intake histories in highly decomposed corpses.","authors":"Fumiya Morioka, Atsushi Nitta, Noriaki Shima, Jun Yoshida, Kazuya Mori, Munehiro Katagi, Takako Sato","doi":"10.1007/s11419-026-00762-7","DOIUrl":"10.1007/s11419-026-00762-7","url":null,"abstract":"<p><p>PURPOSE: This study evaluated the applicability of segmental hair analysis using liquid chromatography-tandem mass spectrometry (LC/MS/MS) to determine the cause of death in highly decomposed corpses, where collection of urine or blood samples was impossible. METHODS: Multiple hair samples were collected from a highly decomposed female corpse and cut into 1-, 3-, and 10-mm segments. Qualitative LC/MS/MS analysis was performed on the hair root and shaft segments, followed by detailed quantitative analysis of the hair fragments. RESULTS: Qualitative analysis detected the prescribed drugs including zolpidem in all segments, indicating a distribution pattern of daily drug intake. Detailed segmental analysis revealed zolpidem concentrations ranging from 30 to 70 pg/mm in the root segment, and from 200 to 400 pg/mm in the other segments. These findings ruled out a large intake of zolpidem immediately prior to death. Similarly, no evidence of acute overdose with other prescribed drugs was identified. CONCLUSION: This study demonstrated that even in decomposed corpses, where conventional biological samples are unavailable, high-sensitivity LC/MS/MS analysis of hair segments, including the root, enables accurate determination not only of the deceased’s routine intake of sleep-inducing drugs but also of immediately pre-mortem drug intake.</p>","PeriodicalId":12329,"journal":{"name":"Forensic Toxicology","volume":" ","pages":"341-348"},"PeriodicalIF":2.1,"publicationDate":"2026-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147510881","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Forensic ToxicologyPub Date : 2026-07-01Epub Date: 2026-02-03DOI: 10.1007/s11419-026-00757-4
Kana Unuma, Toshihiko Aki, Nana Kobayashi, Shintaro Isa, Akihiro Tojo
{"title":"Possible role of ribosome biogenesis in the recovery from transient hepatic damage caused by ethylene glycol in rats.","authors":"Kana Unuma, Toshihiko Aki, Nana Kobayashi, Shintaro Isa, Akihiro Tojo","doi":"10.1007/s11419-026-00757-4","DOIUrl":"10.1007/s11419-026-00757-4","url":null,"abstract":"<p><strong>Purpose: </strong>Ethylene glycol (EG), a widely used industrial compound, has been implicated in accidental poisoning and homicide. Although the nephrotoxic mechanisms of EG are well characterized, its acute hepatotoxic potential remains underexplored. This study investigated histopathological and molecular alterations in the liver of rats following acute administration of EG. Possible dysfunction of an anti-oxidative pathway involving ferroptosis (glutathione peroxidase 4, Gpx4; solute carrier family 7 member 11, SLC7A11) is also examined.</p><p><strong>Methods: </strong>Male rats (8-week-old, male) were orally administered EG (8 g/kg) and euthanized at 2 and 5 days post-exposure by an administration of an overdose of anesthetic (40 mg/kg sodium pentobarbital). Serological analysis was performed to assess liver function. Liver tissues were evaluated by histology, transmission electron microscopy, and transcriptome analysis.</p><p><strong>Results: </strong>Serological findings indicated transient liver damage at 2 days post-exposure, followed by recovery at 5 days. Transmission electron microscopy revealed glycogen accumulation, corroborated by periodic acid-Schiff and periodic acid-methenamine silver staining. Histological analysis revealed an increased number of nucleoli, correlating with upregulation of ribosomal genes on microarray analysis, particularly at 5 days post-exposure. In addition, significant decreases in Gpx4 and SLC7A11 expression were observed in rat livers treated with EG and Huh-7 human hepatoma cells, suggesting reduced cellular antioxidative capacity as a contributing factor to transient liver damage.</p><p><strong>Conclusions: </strong>These findings reveal a pathway underlying EG-induced transient liver damage and suggest a possible mechanism of recovery, thereby providing new insights into EG poisoning.</p>","PeriodicalId":12329,"journal":{"name":"Forensic Toxicology","volume":" ","pages":"313-326"},"PeriodicalIF":2.1,"publicationDate":"2026-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC13303457/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146112716","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Rapid semi-quantitative estimation of cocaine purity by infrared absorption spectroscopy and Raman spectroscopy combined with multivariate analysis.","authors":"Hiroki Segawa, Kenji Tsujikawa, Tadashi Yamamuro, Tatsuyuki Kanamori, Yuko T Iwata","doi":"10.1007/s11419-026-00768-1","DOIUrl":"10.1007/s11419-026-00768-1","url":null,"abstract":"<p><p>PURPOSE: Cocaine is one of the most widely abused drugs, and the analysis of seizures including drug profiling is a critical task for forensic practitioners. Street cocaine samples frequently contain additives, and they could hinder conventional drug analysis. In this study, a multivariate analysis method was made to rapidly estimate the composition and quantity of cocaine and its additives using Fourier transformation-infrared absorption (IR) spectroscopy and Raman spectroscopy. METHODS: IR and Raman spectra of standard cocaine samples and 21 additive samples were acquired. Training dataset was synthetically constructed by making linear combinations of the standard spectra with randomly generated weight and noises. Four different models of non-negative least square regression (NNLS), non-negative matrix factorization (NMF), non-negative elastic net (Enet) and multilayer perceptron (MLP), were constructed. The constructed models were applied to street samples whose components were previously characterized by conventional methods. RESULTS: Though all four methods gave good root-mean-square errors on the training dataset, application to street samples gave different results. NNLS provided the sparsest and the most appropriate results. MLP also provided similar level prediction capability. NMF could not retrieve the original standard spectra. Enet could not give sparse results and application to the street samples showed large fitting residuals. Based on these results, a decision procedure to predict the contents of cocaine seizure was constructed by the combination of NNLS and MLP. CONCLUSION: Vibrational spectroscopy combined with multivariate analysis demonstrated significant potential for the rapid, semi-quantitative prediction of cocaine seizures with the information on diluents/adulterants.</p>","PeriodicalId":12329,"journal":{"name":"Forensic Toxicology","volume":" ","pages":"372-384"},"PeriodicalIF":2.1,"publicationDate":"2026-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147698001","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Forensic ToxicologyPub Date : 2026-07-01Epub Date: 2026-01-27DOI: 10.1007/s11419-026-00758-3
F Palazzoli, P Verri, D Vandelli, A L Fabris, V Castagnetti, G Gualandri, A L Santunione
{"title":"The combined analysis of hair samples with fly larvae for the forensic identification of skeletonized human remains.","authors":"F Palazzoli, P Verri, D Vandelli, A L Fabris, V Castagnetti, G Gualandri, A L Santunione","doi":"10.1007/s11419-026-00758-3","DOIUrl":"10.1007/s11419-026-00758-3","url":null,"abstract":"<p><strong>Purpose: </strong>In the present work, we report the combined use of hair and fly larvae samples as a valuable approach for obtaining additional toxicological evidence in cases of skeletonized corpses. In highly decomposed human remains, the absence of conventional biological specimens (e.g. blood, urine, and organs) requires alternative matrices to base the forensic investigation upon. However, it is challenging to find the most suitable medico-legal approach in these cases.</p><p><strong>Methods: </strong>Hair and fly larvae samples were collected from two independent cases and processed by solid phase extraction using a similar procedure. Analyses were performed using liquid chromatography tandem mass spectrometry.</p><p><strong>Results: </strong>Two anticonvulsants were found in the samples but in a different pattern: phenobarbital in case 1, and phenobarbital in association with phenytoin in case 2.</p><p><strong>Conclusions: </strong>The results of this toxicological approach combining two different samples, hair and larvae, in addition to circumstantial and autopsy findings, proved to be paramount in the medico-legal assessment of the cases herein described, leading to the successful identification of the subjects by DNA analysis. We thus hope that the approach and findings reported in this work contribute to the growing entomotoxicology science and its applicability to real complex forensic cases, especially considering that, to the best of our knowledge, this is the first article describing the determination of phenytoin in insects for this purpose.</p>","PeriodicalId":12329,"journal":{"name":"Forensic Toxicology","volume":" ","pages":"445-451"},"PeriodicalIF":2.1,"publicationDate":"2026-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC13303719/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"146051085","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Forensic ToxicologyPub Date : 2026-07-01Epub Date: 2026-03-03DOI: 10.1007/s11419-026-00759-2
Hiroshi Tsutsumi, Ako Sasao, Ryota Hiraiwa, Kyoko Hirata, Rie Sano
{"title":"Acute high-dose diazepam reduces total bilirubin in bile: an experimental mouse study.","authors":"Hiroshi Tsutsumi, Ako Sasao, Ryota Hiraiwa, Kyoko Hirata, Rie Sano","doi":"10.1007/s11419-026-00759-2","DOIUrl":"10.1007/s11419-026-00759-2","url":null,"abstract":"<p><p>PURPOSE: Acute drug intoxication may impair hepatic conjugation before overt liver failure. This study examined potential conjugation disturbances by assessing changes in serum and biliary bilirubin together with vital signs after an acute high dose of diazepam in mice. METHODS: Male ICR mice (n = 9 per group) received an oral dose of diazepam (720 mg/kg) or vehicle (0.5% carboxymethylcellulose sodium) and were monitored for 120 min. Pulse rate, peripheral capillary oxygen saturation (SpO₂), and respiratory rate were recorded every 5 min using a pulse oximeter. At 120 min, the mice were euthanized by cervical dislocation, and blood and bile were collected. Total bilirubin concentrations in serum and bile were measured using a colorimetric assay with a lower limit of quantification of 0.16 mg/dL. RESULTS: Diazepam-treated mice showed a greater decline in pulse rate than vehicle-treated mice, whereas SpO₂ and respiratory rate showed no significant between-group differences. Serum total bilirubin remained below the lower limit of quantification in all animals. By contrast, biliary total bilirubin concentrations were significantly lower in diazepam-treated mice than in vehicle controls (9.16 ± 0.76 vs. 5.31 ± 0.80 mg/dL, p = 0.01), despite comparable bile weight between groups. CONCLUSIONS: Acute high-dose diazepam selectively reduced biliary total bilirubin without marked hypoxemia or respiratory depression. These findings suggest that biliary bilirubin content may serve as a candidate marker of altered hepatic conjugation during acute diazepam intoxication and warrant further evaluation in analyses of human autopsy bile in forensic toxicology.</p>","PeriodicalId":12329,"journal":{"name":"Forensic Toxicology","volume":" ","pages":"405-410"},"PeriodicalIF":2.1,"publicationDate":"2026-07-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC13303655/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"147344016","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"医学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}