Vladimir Leonidovich Reinyuk

Acute methadone poisoning is a serious socioeconomic problem worldwide. THE AIM OF THE STUDY. was to conduct an epidemiological analysis of the prevalence of acute methadone poisoning cases in St. Petersburg from 2022 to 2024, based on data from a multidisciplinary emergency hospital. MATERIAL AND METHODS. A total of 2,812 medical records and toxicology test results of patients hospitalized with acute methadone poisoning during the specified period were reviewed. The epidemiological analysis included a quantitative assessment of the incidence of acute methadone poisoning among St. Petersburg residents per 100,000 people. RESULTS. The study revealed that over a three-year period, the incidence of acute methadone poisoning among St. Petersburg residents varied unevenly, with a predominance of cases in 2022 and 2023, and a sharp decrease in this indicator in 2024 to 10.8 per 100 thousand population, respectively (c2=36, p=0.0002). Male patients were more often hospitalized with this poisoning. An increase in cases of hospitalization with acute methadone poisoning in patients of working age (from 39 to 48 years old) was noted: from 33.8% to 45.7% by 2024. Over the period from 2022 to 2024, the total number of cases of hospitalization in toxicology departments of patients with acute mild methadone poisoning increased from 31.9% to 52.3% (c2=28.2, p=0.0003). In turn, the proportion of patients requiring assistance in the intensive care unit decreased over this period from 68.1% to 47.7% (c2=17.2, p=0.0001). The proportion of patients requiring mechanical ventilation in the intensive care unit ranged from 76.2% to 90.6% without statistically significant changes over the three-year period (c2=2.89, p=0.09). Among hospitalized patients, isolated methadone use was prevalent, accounting for 70.9% of cases. Combined use of methadone with other psychoactive substances or medications was observed less frequently, in 29.1% of cases. The mortality rate during the study period was 70 cases (case fatality rate — 2.5%). CONCLUSION. The study found a decrease in the incidence of acute methadone poisoning among residents of St. Petersburg from 19.9 to 10.8 per 100,000 people over the period from 2022 to 2024.

This report presents a case of acute severe poisoning with methadone and α-pyrrolidinovalerophenone in a 41-year-old male patient complicated by circulatory arrest. The poisoning occurred following the intravenous injection of 0.5 g of methadone and intranasal administration of α-pyrrolidinovalerophenone. The case manifested as a critical circulatory arrest with a significant depression of consciousness, reaching a coma II level, alongside cytotoxic edema affecting the white matter of the brain and corpus callosum. Notably, the serum S-100 protein concentration was increased to 152.1 ng/L. The patient also exhibited acute respiratory failure, mixed acid-base disorders, lactic acidosis, cardiotoxic effects, acute renal impairment, acute hepatic impairment, toxic encephalopathy, post-cardiac arrest syndrome, and subsequent severe neurocognitive deficits, as well as cystic gliosis and atrophy in the anterior and anterior-basic parts of the frontal lobes, along with cyst formation in the basal nuclei. The patient received intensive care, including mechanical ventilation with the Hamilton C2 device in Continuous Mandatory Ventilation (CMV) mode, inotropic support, correction of acid-base and hypoxic disturbances, and nutritional support via percutaneous endoscopic gastrostomy to address protein-energy deficiency. Additionally, antibacterial therapy was employed, along with measures to resolve intestinal obstruction. Following stabilization of the blood’s oxygen transport function, a multicomponent drug containing inosine, nicotinamide, riboflavin, and succinic acid was used, which facilitated correction of hypoxic complications and the acute psycho-organic syndrome, leading to improvements in cognitive function.

Despite the existing data on dioxin hepatotoxicity, information on the role of gut microbiota and intersystem interactions in the gut-liver axis remains fragmented. Mechanisms linking direct toxic hepatocyte damage, bile outflow disorders (cholestasis) , and aryl hydrocarbon receptor (AhR)–dependent immune modulation to changes in the gut microbiota and progression of fatty liver degeneration lack sufficient systematization. This necessitates a comprehensive reinterpretation of existing data and the identification of gaps in understanding the microbiome-dependent mechanisms of chronic hepatotoxicity. This study aimed to analyze current data on the role of gut microbiota in the development of diffuse liver pathology under chronic dioxin exposure, including the contributions of oxidative stress, lipid peroxidation processes, and immune disorders. The scientific publications for this review were searched and analyzed in both Russian and international reference and bibliographic databases. These included the Russian Science Citation Index, along with international databases such as PubMed, Scopus, Web of Science, and Google Scholar, covering the past 10 years. Using search queries dioxins and dioxin-like compounds, a pool of publications was formed, and works on the toxicokinetics of persistent organic pollutants were selected. Analysis of modern publications devoted to the role of gut microbiota in the pathogenesis of dioxin hepatotoxicity indicates that the liver is one of the key target organs during chronic exposure to these persistent organic pollutants. Aggregated data confirm the leading role of the gut-liver axis in the development of diffuse liver pathology, including the mechanisms of interaction between its components, changes in microbiota, barrier function impairments, immunoinflammatory reactions, and activation of signaling pathways involved in the development of hepatic injuries. The analysis allows for clarifying modern concepts on pathogenetic mechanisms and expanding approaches to the diagnosis of diffuse liver diseases during chronic dioxin exposure. Fatty liver degeneration under the influence of hepatotoxicants results from the interaction of xenobiotics with liver enzymes, microbiota, and immune mechanisms. Toxicants often transform into more harmful metabolites that enhance oxidative stress and hepatocyte damage. Impaired microbiota and bile acid metabolism intensify inflammation and fibrosis. Persistent pollutants activate AhR and alter cytochrome P450 activity, which contributes to the formation of chronic toxic liver damage.

BACKGROUND: For many years, methadone poisoning has remained one of the leading causes of death among patients admitted to toxicology departments worldwide. During the COVID-19 pandemic, the number of such patients increased substantially, which may be associated with heightened anxiety, fear, sadness, adaptation difficulties, symptoms of post-traumatic stress disorder, and suicidal tendencies in both the general population and specific subgroups, thereby increasing the risk of drug and alcohol use as maladaptive coping strategies. AIM: To perform a comparative analysis and evaluate the results of methadone detection based on retrospective data from chemical toxicological and forensic chemical investigations conducted in 2020–2022. METHODS: This cross-sectional multicenter sample study employed retrospective medical data from patients who died of acute methadone poisoning. The analysis assessed features of methadone detection in fatal acute poisonings, the comparability of chemical toxicological and forensic chemical investigation results, and the frequency of circumstances affecting interpretation of the obtained findings. RESULTS: The study included data from 131 cases of fatal methadone poisoning. In all reviewed cases, screening in chemical toxicological investigations was performed using immunochromatographic assay. In 20% of cases, the assay was performed 12–48 hours after hospital admission. False-positive methadone detection results in chemical toxicological investigations were recorded in 3.4% of cases, whereas false-negative results were found in 6%. In addition, confirmatory methods were not used in 18% of cases. Moreover, in all cases with false-negative results, high concentrations of substances such as nicotine and caffeine were detected in the samples, which may have affected the reliability of immunochromatographic assay. CONCLUSION: Improving approaches to the selection of biological material, the timing of assay, and the mandatory use of confirmatory methods may minimize the risk of false-positive and false-negative methadone test results in chemical toxicological investigations. This, in turn, may improve diagnostic accuracy, optimize treatment strategy, and provide a more objective assessment of medical circumstances in subsequent forensic medical examinations.

The features of the clinical course and the main outcomes at different stages of acute poisoning with barbituric acid preparations are considered.The databases of the Russian National Library, PubMed, Medline, Medscape, eLIBRARY.RU, CyberLeninka were analyzed.During barbiturate poisoning, it is customary to distinguish four consecutive stages depending on the concentration of the substance in the blood, each of which may be accompanied by the development of certain life-threatening conditions. The risk of developing critical conditions is due to a combination of poisoning with another etiology, the presence of concomitant pathology.The complications and outcome of acute barbiturate poisoning largely depend on both the severity of the poisoning and the individual patient profile.Authors’ contribution: Demidova E.O. – research concept, collection and processing of material, writing, editing; Reinyuk V.L. – writing, editing; Kuznetsov S.V. – writing, editing; Klimenko D.I. – writing, editing. All co-authors are responsible for approving the final version of the article and ensuring the integrity of all its parts.Conflict of interests. The authors declare no apparent and potential conflicts of interest in relation to the publication of this article.Funding. The study had no sponsorship.Accepted: January 14, 2025 / Revised: March 26, 2025 / Received: November 25, 2025 / Published: January 15, 2026

Introduction. Soil is an important element of the city’s ecological system. Therefore, in the russian federation and european countries, in-depth studies are being conducted to substantiate permissible levels of soil exposure for most known metals. The level of environmental pollution varies in different parts of the city and may depend on the distance from the source of pollution, such as an industrial enterprise. The studied industrial center of the russian federation has areas that differ in functional use and purpose, including a large industrial enterprise, which is one of the key complexes of russian chemical production.The purpose of this study is to determine the content of a number of metals (mercury, lead, zinc, arsenic, chromium, nickel, cobalt, copper, manganese, barium, vanadium) in the soil of different areas of one of the industrial centers of the Russian Federation.Material and methods. The paper presents the results of determining chemical elements (metals) in the soil of different urban areas of one of the industrial centers of the Russian Federation. Soil samples taken in 10 areas of the city were analyzed for quantitative content of metals using inductively coupled plasma mass spectrometry. The samples were collected over a period of two years; the research method was inductively coupled plasma mass spectrometry.Results. The results of the study showed that in all the studied areas of the city, metal contents (Pb, Zn, Cu and As) were found that exceeded the permissible levels approved in the Russian Federation, which indicates a potential threat to the health of the population living in these territories.Limitation. The use of these research methods is possible only in a specially equipped laboratory with qualified personnel.Conclusion. The detected concentrations emphasize the importance of regular monitoring of the content of hazardous metals in the soil. An opinion has been formed on the need to take measures to reduce chemical pollution and the impact on the environment and to continue research, especially in those areas where excess exposure levels have been identified. The standards (maximum permissible concentrations) approved in the Russian Federation and similar standards (maximum permissible concentrations) of the Netherlands are compared.Compliance with ethical standards. This study does not require the conclusion of a biomedical ethics committee or other documents.Authors’ contribution: Varioshkin P.N. – concept and design of the study, collection of material and data processing, statistical processing, writing the text; Lukovnikova L.V. – data processing, writing; Reynyuk V.L. – data processing, editing; Kombarova M.Yu. – collection of material and data processing, statistical processing; Kuznetsov S.V. – collection of material and data processing, statistical processing; Yatselenko Yu.V. – data processing, editing. All co-authors – approval of the final version of the article, responsibility for the integrity of all parts of the article.Conflict of interests. The authors declare no conflicts of interest.Funding. The study was supported by the Golikov Research Clinical Center of Toxicology of the FMBA of Russia, Saint Petersburg, Russian Federation.Received: August 21, 2025 / Revised: September 03, 2025 / Accepted: October 2, 2025 / Published: November 19, 2025

Circumstances of deaths in water are diverse, encompassing both relatively typical drowning cases and rarer causes such as injury from electrogenic aquatic animals. It is not uncommon for medical assistance rendered during or immediately after a water-related incident to contain errors that may result in an unfavorable outcome. The article presents a detailed analysis of a representative case of asphyxia in a child in a swimming pool, which resulted in death 16 days later in a hospital setting. The sequence of medical interventions—from prehospital to specialized care—is described. Special attention is given to the interaction with investigative authorities in distinguishing between possible circumstances of death: drowning versus inadequate resuscitative measures. The necessity of interpreting potential iatrogenic complications strictly within the context of the initial cause of medical intervention is emphasized. The importance of strict adherence to water safety rules is also highlighted. The article identifies contentious aspects of legal qualification in such cases and underscores the lack of a unified methodology for their forensic evaluation. Shortcomings commonly observed in forensic medical examinations of similar situations are noted, emphasizing the inadmissibility of a formal approach. Directions for improving expert practice and eliminating identified disadvantages are proposed.

The article discusses the controversial aspects of conducting medical examinations for intoxication. This work is based on a case report on determining the legitimacy of administrative license revocation, which involved a forensic medicine and toxicology expert. A detailed chronology is provided, from the moment the driver was stopped by a traffic police officer and suspended from driving for an alcohol intoxication test, to the ruling by the magistrates’ court, which was later upheld by the court of cassation. This case study illustrates errors in interpreting the findings of chemical tests for intoxication, which occur when psychoactive substances are incorrectly identified in human biological fluids. This case of γ-butyrolactone detection in a professional car driver highlights the inadmissibility of unreliable methods for chemical compound identification. Moreover, the paper emphasizes insufficient training of clinical laboratory diagnostics physicians, addresses the issue of an overly mechanistic approach to their work, and proposes potential solutions to the identified shortcomings.

BACKGROUND: Modern scientific data show that only 1.1% die from methadone poisoning in medical institutions. Currently available forensic medical data about this nosology were produced from samples obtained from corpses of individuals who has not undergone any previous therapeutic and diagnostic procedure. The dynamics and role of metabolic disorders in the thanatogenesis of acute methadone poisoning and the forensic assessment of such cases have not been widely studied in forensic medicine. AIM: To perform a forensic medical assessment of fatal cases of acute methadone poisoning in patients admitted to a multidisciplinary hospital and establish the role of metabolic disorders in the occurrence of death. MATERIALS AND METHODS: A single-center, retrospective, sample, cohort study was conducted. Medical records and data from forensic medical reports were examined. All included observations with a positive determination of methadone were confirmed in the framework of lifetime chemical and toxicological studies and during postmortem forensic chemical studies of the biological environment of corpses. For the final interpretation of the results and evaluation of their statistical significance, the Pearson’s Chi-square (χ2) criterion was used. RESULTS: A comparative analysis of clinical and forensic data from most cases revealed consistent causes of death established in vivo and posthumously. Moreover, the leading pathological process that led to death was a combination of pulmonary and cerebral edema. The variability in the causes of death in some cases was due to the background pathology determined by thanatogenesis. The life expectancy of patients was determined by the effectiveness of intensive therapy (ventilator, infusion therapy, vasopressor, inotropic support, correction of metabolic disorders) and characterized by background pathologies and duration of hospital stay. CONCLUSION: A number of main and related conclusions of practical forensic and clinical interest were drawn from obtained data. Notably, in all cases, the fatal outcome of methadone poisoning was associated with metabolic disorders and severe hypoxia. Moreover, the use of antidote therapy with naloxone and wait-and-see techniques without respiratory support in the treatment of such patients is unreasonable.

Introduction. Currently in the Russian Federation, the practice of industrial medicine does not use methods of biological monitoring of organic compounds – an addition to industrial control, which consists in regularly measuring the content of biomarkers of harmful chemicals in the body of workers. The purpose of the study is to analyze available scientific publications and methodological documents on biomarkers of harmful organic substances, to draw conclusions about the directions for the development of methodological support for biological monitoring of organic compounds in the Russian Federation. Material and methods. available scientific publications, methodological guidelines of Rospotrebnadzor, materials of the Russian Register of Potentially Hazardous Chemical and Biological Substances, and foreign methodological documents, in particular from the Agency for Toxic Substances and Disease Registry, USA, were used. Results. A list of the most common harmful organic substances circulating at hazardous chemical facilities, their biomarkers and methods for measuring them in biological media was compiled. An analysis of domestic and foreign hygienic standards for the content of toxicants or their markers in biological media was performed. Limitations. The analytical review of biological monitoring methods was carried out only for organic compounds and does not include inorganic substances. Conclusion. The analytical review made it possible to identify the following necessary methodological elements for the implementation of biological monitoring in the Russian Federation: the development of at least 9 chemical-analytical methods for determining biomarkers in the biological environments of workers, the introduction of immunochromatographic methods when conducting biological monitoring of workers to clarify the reliability of anamnesis data on attitudes towards alcohol, smoking and medications, experimental studies on the detection and identification of biomarkers of exposure to a number of organic compounds, experimental substantiation of hygienic standards for the content of 15 substances in the air of the working area.