A Rare Case of Suicide by Ingestion of Phorate: A Case Report and a Review of the Literature

Mitochondrial Impact of Organophosphate Pesticide-Induced Cardiotoxicity: An In Silico and In Vitro Study

Organophosphate pesticides are widely used; however, their use is limited due to neurotoxicity and, to a lesser extent, cardiotoxicity in humans. Given the high energy demands of cardiac muscle, which is characterized by a dense population of mitochondria, any damage to these organelles can exacerbate cardiotoxicity. This study aims to elucidate whether the cardiotoxic effects of organophosphate pesticides originate from mitochondrial dysfunction. To investigate this, in silico toxicogenomic analyses were performed using various tools, such as the Comparative Toxicogenomic Database, GeneMANIA, STRING, and Cytoscape. Results revealed that 11 out of the 13 WHO-recommended Class Ia organophosphate pesticides target genes associated with cardiotoxicity. Notably, three of these genes were mitochondrial, with catalase (CAT) being the common differentially expressed gene among parathion, methyl parathion, and phorate. Furthermore, protein-protein interaction analysis indicated a strong association between CAT and superoxide dismutase 2, mitochondrial (SOD2). Subsequently, isolated heart mitochondria were utilized to assess CAT and superoxide dismutase (SOD) activities in vitro. The findings demonstrated that at a concentration of 7.5 ng/µL, both methyl parathion and phorate significantly decreased CAT activity by approximately 35%. Moreover, phorate reduced total SOD and SOD2 activities by 17% and 19%, respectively, at the same concentration. In contrast, none of the three organophosphate pesticides induced the opening of the mitochondrial permeability transition pore. These results suggest that the reduction in CAT and SOD2 activities, critical antioxidant enzymes, leads to the accumulation of reactive oxygen species within mitochondria, ultimately resulting in mitochondrial damage. This mechanism likely underlies the observed cardiotoxicity induced by these organophosphate pesticides.

Preparation of Hybrid Magnetic Nanoparticles for Sensitive and Rapid Detection of Phorate Residue in Celery Using SERS Immunochromatography Assay

Extensive use of pesticides in agricultural production has been causing serious health threats to humans and animals. Among them, phorate is a highly toxic organophosphorus insecticide that has been widely used in planting. Due to its harmful effects on human and animal health, it has been restricted for use in many countries. Analytical methods for the rapid and sensitive detection of phorate residues in agricultural products are urgently needed. In this study, a new method was developed by combining surface-enhanced Raman spectroscopy (SERS) and immunochromatography assay (ICA). Hybrid magnetic Fe3O4@Au@DTNB-Ab nanoprobes were prepared by modifying and growing Au nanoseeds on an Fe3O4 core. SERS activity of the nanoprobe was optimized by adjusting the concentration of the Au precursor. A rapid and sensitive assay was established by replacing the traditional colloidal gold-based ICA with hybrid SERS nanoprobes for SERS-ICA. After optimizing parameters including coating antibody concentrations and the composition and pH of the buffer solution, the limit of detection (LOD) for phorate could reach 1 ng/mL, with a linear range of 5~100 ng/mL. This LOD is remarkably lower than the maximum residue limit in vegetables and fruits set by the Chinese government. The feasibility of this method was further examined by conducting a spiking test with celery as the real sample. The result demonstrated that this method could serve as a promising platform for rapid and sensitive detection of phorate in agricultural products.

Effects of aluminium phosphide on larval morphometry of two important Chrysomya species

Chrysomya megacephala and C. rufifacies are globally predominant species of blowflies that are amongst the primary colonisers of decomposing carcasses. The development of blowflies has been studied extensively to estimate the minimum postmortem interval (PMImin). This article evaluates the effect of aluminium phosphide (AlP) on the larval morphometry and life cycles of C. megacephala and C. rufifacies. The rabbits were given different dosages of AlP and their livers were excised to rear C. megacephala and C. rufifacies. Through multiple-regression analysis, we assessed the overall impact of varying dosages of AlP on larvae of both species. AlP accelerated development until pupation, whilst the time until emergence remained the same. At higher concentrations, AlP had a positive effect on the development of these species. Since both species are abundant, forensic entomology studies examining the effect of AlP on morphometry and developmental stages would provide valuable information to investigators assessing PMImin.

The impact of the use of personal-protective-equipment on the minimization of effects of exposure to pesticides among farm-workers in India

Introduction

Although excessive use of pesticides and unsafe agricultural practices may contribute to numerous intoxications, the role of PPE (personal-protective-equipment) in the minimization of toxicological effects due to pesticide exposure has not been addressed so far. The present study aimed to assess the impact of the use of PPE on the minimization of effects of exposure to pesticides among farm-workers.

Methods

A community-based follow-up study with questionnaire-based survey and field observations was undertaken among farm-workers (n = 180) of Rangareddy district, Telangana, India. Biomarkers of exposure such as cholinesterase activity, inflammatory markers (TNF-α, IL-1β, IL-6, cortisol, and hs-C reactive protein), nutrients (vitamins A, E), liver function (total protein and A/G ratio, AST and ALT levels) were investigated in the laboratory by following the standard protocols.

Results

Farm-workers who had a mean farming exposure of 18 years of and who neither followed safe pesticide handling practices nor used PPE and also showed reluctance to obey good agricultural practices (GAPs). Inhibition of AChE (acetylcholine esterase) with increased inflammation was found among farm-workers as compared to their respective normal values when they have not used PPE. Linear regression statistical analysis revealed a profound effect on inhibition in the AChE activity and various inflammatory markers with the increase in the duration of pesticide exposure. Further, there was no effect of the duration of pesticide exposure on the levels of vitamins A, E, ALT, AST, total protein, and A/G ratio. Further, intervention studies carried out on the use of PPE provided (commercially available and cost-effective) for 90 days showed a significant reduction in the biomarker levels (p < 0.01).

Conclusion

This study demonstrated the importance of the use of PPE during pesticide applications and other agricultural tasks to minimize pesticide-associated adverse health effects.

Suicide by Pesticide (Phorate) Ingestion: Case Report and Review of Literature

It has been estimated that approximately one in seven of all global suicides is due to pesticide self-poisoning, mostly in rural areas of developing countries. Organophosphorus (OP) compounds are a group of pesticides exerting their toxicological effects through non-reversible inhibition of the enzyme acetylcholinesterase (AChE). Among these compounds, phorate (thimet) is one of the most dangerous compounds, the use of which is restricted in many countries. A case of intentional suicide after phorate ingestion in a 24-year-old Bengali male is described. This is the second case of suicidal ingestion of phorate reported in the forensic literature, and the first presenting complete toxicological findings.

Advances in organophosphorus pesticides pollution: Current status and challenges in ecotoxicological, sustainable agriculture, and degradation strategies

Organophosphorus pesticides (OPPs) are one of the most widely used types of pesticide that play an important role in the production process due to their effects on preventing pathogen infection and increasing yield. However, in the early development and application of OPPs, their toxicological effects and the issue of environmental pollution were not considered. With the long-term overuse of OPPs, their hazards to the ecological environment (including soil and water) and animal health have attracted increasing attention. Therefore, this review first clarified the classification, characteristics, applications of various OPPs, and the government's restriction requirements on various OPPs. Second, the toxicological effects and metabolic mechanisms of OPPs and their metabolites were introduced in organisms. Finally, the existing methods of degrading OPPs were summarized, and the challenges and further addressing strategy of OPPs in the sustainable development of agriculture, the environment, and ecology were prospected. However, methods to solve the environmental and ecological problems caused by OPPs from the three aspects of use source, use process, and degradation methods were proposed, which provided a theoretical basis for addressing the stability of the ecological environment and improving the structure of the pesticide industry in the future.

Pharmacogenetics and Forensic Toxicology: A New Step towards a Multidisciplinary Approach

Pharmacogenetics analyzes the individual behavior of DNA genes after the administration of a drug. Pharmacogenetic research has been implemented in recent years thanks to the improvement in genome sequencing techniques and molecular genetics. In addition to medical purposes, pharmacogenetics can constitute an important tool for clarifying the interpretation of toxicological data in post-mortem examinations, sometimes crucial for determining the cause and modality of death. The purpose of this systematic literature review is not only to raise awareness among the forensic community concerning pharmacogenetics, but also to provide a workflow for forensic toxicologists to follow in cases of unknown causes of death related to drug use/abuse. The scientific community is called on to work hard in order to supply evidence in forensic practice, demonstrating that this investigation could become an essential tool both in civil and forensic contexts. The following keywords were used for the search engine: (pharmacogenetics) AND (forensic toxicology); (pharmacogenetics) AND (post-mortem); (pharmacogenetics) AND (forensic science); and (pharmacogenetics) AND (autopsy). A total of 125 articles were collected. Of these, 29 articles were included in this systematic review. A total of 75% of the included studies were original articles (n = 21) and 25% were case reports (n = 7). A total of 78% (n = 22) of the studies involved deceased people for whom a complete autopsy was performed, while 22% (n = 6) involved people in good health who were given a drug with a subsequent pharmacogenetic study. The most studied drugs were opioids (codeine, morphine, and methadone), followed by antidepressants (tricyclic antidepressants and venlafaxine). Furthermore, all studies highlighted the importance of a pharmacogenetics study in drug-related deaths, especially in cases of non-overdose of drugs of abuse. This study highlights the importance of forensic pharmacogenetics, a field of toxicology still not fully understood, which is of great help in cases of sudden death, deaths from overdose, deaths after the administration of a drug, and also in cases of complaint of medical malpractice.

Biodegradation of phorate by bacterial strains in the presence of humic acid and metal ions

Phorate is a systemic insecticide used to eradicate mites, insects, and nematodes. Extensive use of this organophosphate has engendered severe environmental concerns. The current research aimed to explore the kinetic pathways of phorate biodegradation in aqueous solutions. Two novel bacterial strains Pseudomonas aeruginosa strain PR1 (KP268772.1) and Pseudomonas sp. PR_02 (KP268773.1) were isolated, screened, and developed given their potential to degrade phorate. Mineralization of phorate was assayed with and without the addition of metal ions [Fe (II) and Cu (II)] and humic acid (HA). In 14 days, experiment both strains have consumed about 69%-94.5% (half-life from 3.58 to 6.02 days) of phorate. The observed biodegradation rate of phorate with Cu (II) in the system was 73% and 87%, with a half-life of 4.86 and 4.07 days for PR1 and PR2, respectively. The biodegradation of phorate using Fe(II) was 69% and 82%, with half-life periods 5.68 and 4.49 days. Meanwhile, incorporating HA, the phorate biodegradation was inhibited significantly, showing 71% and 85% degradation, with half-life periods of 6.02 and 5.02 days. The results indicated that both bacterial strains were able to mineralize phorate with PR2 > PR1. Summarizing, the inhibition in phorate biodegradation order under different conditions was as HA > Fe (II) > Cu (II). UV-visible measurements and gas chromatography-mass spectrometric assays indicated that the possible degradation pathway of phorate included ethoxy-phosphonothio-methanethiol S-mercaptomethyl-O,O-dihydrogen phosphorodithioate, diethyl-methylphosphonate, methane dithiol, ethanethiol, and phosphate, as the main metabolites identified. Therefore, it was concluded that the newly isolated Pseudomonas strains could be a potential candidates for biodegradation of phorate in a cost-effective, safe, and environmentally friendly alternative.

Multidisciplinary Approach to Suspected Sudden Death Caused by Arteriovenous Malformation Rupture: A Case Report

Arteriovenous malformations (AVMs) are rare congenital conditions with a prevalence of less than 1% and are mostly asymptomatic. However, these malformations can suddenly cause intense pain or bleeding, leading to life-threatening medical problems. This report presents a case of an unexpected death in a 37-year-old previously healthy woman due to an intra-cerebellum arteriovenous malformation rupture identified during autopsy. While infective processes where preliminarily excluded, a Post Mortem Computed Tomography (PMCT) identified a tetra ventricular hemorrhage and intra-cerebellum hemorrhage. Toxicological examination was negative for most substances of abuse. During autopsy an intense hemorrhagic infiltrate in the subarachnoid space was observed. After formalin fixation of the brain the cerebellum showed hemorrhagic infarction on fourth ventricle sides, as well as several small reddish infarctions across the entire cerebellum parenchyma. Histological examination of the brain and cerebellum showed a suffusion of erythrocytes in the sub-arachnoid region. Evidence of an arterio-venous malformation, with several intertwine vessels of variable diameter, surrounded by hemorrhagic evidence. The autopsy played a crucial role in identifying the location and the possibly affected vessel, as well as defining the cause of death. It is necessary to have a greater number of autopsies to make an epidemiological contribution. Furthermore, it is crucial to create a multicenter data network with other authors from other departments to improve information about epidemiological, clinical, diagnostic and therapeutic data. Most brain AVMs as cause of death are often undiscovered.