The history of poisoning: from ancient times until modern ERA

Ṯābit Ibn Qurrah's contributions to toxicology

Mankind has been familiar with poisons since ancient times. On the other hand, there is a wealth of knowledge in the medical books including medieval works of Middle Eastern polymaths such as Avicenna, "al-Rāzī," and "Ṯābit Ibn Qurrah." This study presented and analyzed the knowledge of medical toxicology in one of the mainstay works of "Ṯābit Ibn Qurrah" entitled "al-Ḏaḫirah Fy Ꜥilm al-Tibb" also known as The Treasury of Medicine after the translation of the book from Arabic to English carefully and faithfully. Also, related toxicological literature was applied wherever required using English, Arabic, and Persian databases including Scopus, PubMed, Web of Science, WorldCat, Magiran, IranDoc, Scientific Information Database, Noor Mags, Noorlib, and Al Manhal. Our research revealed that chapter 25 of the mentioned book specifically focused on toxicology. This chapter was divided into sections on different aspects of toxicology from the categorization of poisons to compound mixtures causing poisonings to introducing blade poisons to signs and symptoms of poisonings, preventive approaches, and therapeutic agents. Specific antidotes and general therapies were introduced that included medicinal plants, cupping therapy, and bandages, just to name a few. Also, there were some monographs on the common poisonous agents and their treatments. The toxicological data of the book was comparable with modern toxicology. Our study highlighted the contributions of "Ṯābit Ibn Qurrah" to medical toxicology by authoring The Treasury of Medicine. Further research is recommended to elucidate the full aspects of the history of toxicology including the contributions of the past scholars.

Toxic Plants and Their Impact on Livestock Health and Economic Losses: A Comprehensive Review

Plants are important components in sustaining the life of humans and animals, balancing ecosystems, providing animal feed and edible food for human consumption, and serving as sources of traditional and modern medicine. However, plants can be harmful to both animals and humans when ingested, leading to poisoning regardless of the quantity consumed. This presents significant risks to livestock health and can impede economic growth. In several developing countries, including Ethiopia, traditional communities have depended on medicinal plants for treating livestock and human diseases. The incidences of livestock poisoning from medicinal and poisonous plants are due to the misuse and lack of dosage standardization. Therefore, this paper aimed to review toxic plants and their effects on livestock health and associated economic losses. Toxic plants contain secondary metabolites that serve as a defense mechanism against predators. The most common secondary metabolites of toxic plants that affect livestock health and the economy include alkaloids (Asteraceae, Convolvulaceae, Lamiaceae, Fabaceae, and Boraginaceae), cyanides (Sorghum spp. and grass spp.), nitrates (Pennisetum purpureum roots, Amaranthus, nightshades, Solanum spp. Chenopodium spp., and weed spp.), oxalates (Poaecea, Amaranthaceae, and Polygonaceae), and glycosides (Pteridium aquiline). The most common effects of toxic plants on livestock health include teratogenic and abortifacient (Locoweeds, Lupines, Poison Hemlock, and Veratrum), hepatoxicity (Crotalaria, Lantana camara, Xanthium, and Senecio), photosensitization (L. camara, Alternanthera philoxeroides, Brachiaria brizantha, and Heracleum sphondylium), and impairing respiratory and circulatory systems (nitrite and cyanide toxic). Toxic plants lead to substantial economic losses, both direct and indirect. Direct losses stem from livestock deaths, abortions, decreased milk quality, and reduced skin and hide production, while indirect losses are associated with the costs of treatment and management of affected animals. Overall, toxic plants negatively impact livestock health and production, resulting in significant economic repercussions. Therefore, it is crucial to prioritize the identification of the most prevalent toxic plants, isolate secondary metabolites, conduct toxicity tests, standardize dosages, and develop effective strategies for managing both the toxic plants and their associated toxicity.

Pattern of bioterrorism in ancient times: lessons to be learned from the microbial and toxicological aspects

The current research aimed to analyze the history of bioterrorism in antiquity and to adapt the data to modern medical knowledge. To this end, a thorough evaluation of the literature related to the ancient history of bioterrorism and modern data was done using the Web of Sciences, Science Direct, Scopus, PubMed, and Google Scholar. Results showed that knowledge of bioterrorism has existed since antiquity in different civilizations. Biological and toxicological agents were used as an instrument of legal execution, as a warfare tool in battles, or to eliminate political rivals across nations. Ancient people researched bioterrorism to apply it against enemies and at the same time provide countermeasures in favor of themselves and allies. Despite the existence of the principles of bioterrorism since ancient times, adaptation of the data to modern research can assist in planning countermeasure efforts, preventive actions, and treatments in the framework of modern counterterrorism medicine.

Synthesis and in vitro assessment of the reactivation profile of clinically available oximes on the acetylcholinesterase model inhibited by A-230 nerve agent surrogate

The risk of the use of toxic chemicals for unlawful acts has been a matter of concern for different governments and multilateral agencies. The Organisation for the Prohibition of Chemical Weapons (OPCW), which oversees the implementation of the Chemical Weapons Convention (CWC), considering recent events employing chemical warfare agents as means of assassination, has recently included in the CWC "Annex on Chemicals" some organophosphorus compounds that are regarded as acting in a similar fashion to the classical G- and V-series of nerve agents, inhibiting the pivotal enzyme acetylcholinesterase. Therefore, knowledge of the activity of the pyridinium oximes, the sole class of clinically available acetylcholinesterase reactivators to date, is plainly justified. In this paper, continuing our research efforts in medicinal chemistry on this class of toxic chemicals, we synthesized an A-230 nerve agent surrogate and applied a modified Ellman's assay to evaluate its ability to inhibit our enzymatic model, acetylcholinesterase from Electrophorus eel, and if the clinically available antidotes are able to rescue the enzyme activity for the purpose of relating the findings to the previously disclosed in silico data for the authentic nerve agent and other studies with similar A-series surrogates. Our experimental data indicates that pralidoxime is the most efficient compound for reactivating acetylcholinesterase inhibited by A-230 surrogate, which is the opposite of the in silico data previously disclosed.

A personal view on the history of toxins: From ancient times to artificial intelligence

Bioactive substances found in plants, microorganisms and animals have fascinated mankind since time immemorial. This review will focus on the progress that has been made over the centuries and our growing insights. The developments relate to both the discovery and characterization of novel bioactive substances, as well as the ceaseless implementation of refined techniques, the use of high-end instruments and breakthroughs in artificial intelligence with deep learning-based computational methods. As these approaches possess great translational potential, with many applications in different fields, such as therapeutic, diagnostic and agrochemical use, there is a good rationale to continue investing in toxinology-related research.

Reliable Detection of Chemical Warfare Agents Using High Kinetic Energy Ion Mobility Spectrometry

High Kinetic Energy Ion Mobility Spectrometers (HiKE-IMS) ionize and separate ions at reduced pressures of 10-40 mbar and over a wide range of reduced electric field strengths E/N of up to 120 Td. Their reduced operating pressure is distinct from that of conventional drift tube ion mobility spectrometers that operate at ambient pressure for trace compound detection. High E/N can lead to a field-induced fragmentation pattern that provides more specific structural information about the analytes. In addition, operation at high E/N values adds the field dependence of ion mobility as an additional separation dimension to low-field ion mobility, making interfering compounds less likely to cause a false positive alarm. In this work, we study the chemical warfare agents tabun (GA), sarin (GB), soman (GD), cyclosarin (GF) and sulfur mustard (HD) in a HiKE-IMS at variable E/N in both the reaction and the drift region. The results show that varying E/N can lead to specific fragmentation patterns at high E/N values combined with molecular signals at low E/N. Compared to the operation at a single E/N value in the drift region, the variation of E/N in the drift region also provides the analyte-specific field dependence of ion mobility as additional information. The accumulated data establish a unique fingerprint for each analyte that allows for reliable detection of chemical warfare agents even in the presence of interfering compounds with similar low-field ion mobilities, thus reducing false positives.

Smart Sensing of Nerve Agents

The recent international scenario highlights the importance to protect human health and environmental quality from toxic compounds. In this context, organophosphorous (OP) Nerve Agents (NAs) have received particular attention, due to their use in terrorist attacks. Classical instrumental detection techniques are sensitive and selective, but they cannot be used in real field due to the high cost, specialized personnel requested and huge size. For these reasons, the development of practical, easy and fast detection methods (smart methods) is the future of this field. Indeed, starting from initial sensing research, based on optical and/or electrical sensors, today the development and use of smart strategies to detect NAs is the current state of the art. This review summarizes the smart strategies to detect NAs, highlighting some important parameters, such as linearity, limit of detection and selectivity. Furthermore, some critical comments of the future on this field, and in particular, the problems to be solved before a real application of these methods, are provided.

Toxicokinetic analysis of the highly toxic nerve agent VX in commercially available multi-organ-chips - Ways to overcome compound absorption

Organ-on-a-chip technology is considered a next-generation platform in pharmacology and toxicology. Nevertheless, this novel technology still faces several challenges concerning the respective materials which are used for these microfluidic devices. Currently available organ-chips are most often based on polydimethylsiloxane (PDMS). However, this material has strong limitations regarding compound binding. The current study investigated options to reduce compound absorption of the highly toxic nerve agent VX (1000 µmol/L) in a commercially available organ-chip. In addition, surface effects on degradation products of VX were investigated. The alternative polymer cyclic olefin copolymers (CoC) showed significantly less compound absorption compared to PDMS. Furthermore, a coating of PDMS- and CoC-based chips was investigated. The biocompatible polymer polyethyleneimine (PEI) successfully modified PDMS and CoC surfaces and further reduced compound absorption. A previously examined VX concentration after 72 h of 141 ± 10 µmol/L VX could be increased to 442 ± 54 µmol/L. Finally, the respective concentrations of VX and degradation products accounted for > 90% of the initial concentration of 1000 µmol/L VX. The currently described surface modification might be a first step towards the optimization of organ-on-a-chip surfaces, facilitating a better comparability of different studies and results.

DFT-Spectroscopy Integrated Identification Method on Unknown Terrorist Chemical Mixtures by Incorporating Experimental and Theoretical GC-MS, NMR, IR, and DFT-NMR/IR Data

In the event of a chemical attack, the rapid identification of unknown chemical agents is critical for an effective emergency response and treatment of victims. However, identifying unknown compounds is difficult, particularly when relying on traditional methods such as gas and liquid chromatography-mass spectrometry (GC-MS, LC-MS). In this study, we developed a density functional theory and spectroscopy integrated identification method (D-SIIM) for the possible detection of unknown or unidentified terrorist materials, specifically chemical warfare agents (CWAs). The D-SIIM uses a combination of GC-MS, nuclear magnetic resonance (NMR) spectroscopy, infrared (IR) spectroscopy, and quantum chemical calculation-based NMR/IR predictions to identify potential CWA candidates based on their chemical signatures. Using D-SIIM, we successfully verified the presence of blister and nerve agent simulants in samples by excluding other compounds (ethyl propyl sulfide and methylphosphonic acid), which were predicted to be candidates with high probability by GC-MS. The findings of this study demonstrate that the D-SIIM can detect substances that are likely present in CWA mixtures and can be used to identify unknown terrorist chemicals.

From resistance to resilience: Uncovering chemotherapeutic resistance mechanisms; insights from established models

Despite the tremendous advances in cancer treatment, resistance to chemotherapeutic agents impedes higher success rates and accounts for major relapses in cancer therapy. Moreover, the resistance of cancer cells to chemotherapy is linked to low efficacy and high recurrence of cancer. To stand up against chemotherapy resistance, different models of chemotherapy resistance have been established to study various molecular mechanisms of chemotherapy resistance. Consequently, this review is going to discuss different models of induction of chemotherapy resistance, highlighting the most common mechanisms of cancer resistance against different chemotherapeutic agents, including overexpression of efflux pumps, drug inactivation, epigenetic modulation, and epithelial-mesenchymal transition. This review aims to open a new avenue for researchers to lower the resistance to the existing chemotherapeutic agents, develop new therapeutic agents with low resistance potential, and establish possible prognostic markers for chemotherapy resistance.

Elimination of A-234 from the environment: Effect of different decontaminants

With the fact that there are Novichoks in the list of toxic chemicals by the Chemical Weapons Convention parties, it is necessary to develop methods of effective neutralization of the agents as well as for other organophosphorus toxic substances. However, experimental studies on their persistence in the environment and effective decontamination measures remain scarce. Therefore, here, we investigated the persistence behavior and decontamination methods of A-234 (ethyl N-[1-(diethylamino)ethylidene]phosphoramidofluoridate), a Novichok series, A-type nerve agent to assess its potential risk to the environment. Different analytical methods were implemented, including ³¹P solid-state magic angle spinning nuclear magnetic resonance (NMR), liquid ³¹P NMR, gas chromatography-mass spectrometry (GC-MS), liquid chromatography-mass spectrometry, and vapor-emission screening using a microchamber/thermal extractor with GC-MS. Our results showed that A-234 is extremely stable in sand and poses a long-lasting risk to the environment even when released in trace quantities. Moreover, the agent is not easily decomposed by water, dichloroisocyanuric acid sodium salt, sodium persulfate, and chlorine-based water-soluble decontaminants. However, it is efficiently decontaminated by Oxone® monopersulfate, calcium hypochlorite, KOH, NaOH, and HCl within 30 min. Our findings provide valuable insights for eliminating the highly dangerous Novichok agents from the environment.

A Clinical-Epidemiological Study on Beta-Blocker Poisonings Based on the Type of Drug Overdose

Background

Beta-blockers carry a high risk of potentially causing fatal poisoning if overdosed. We aimed to assess the clinical and epidemiological characteristics of patients with beta-blocker poisoning.

Methods

Patients were categorized based on the type of drug poisoning into propranolol, other beta-blockers, and the combination of beta-blocker groups, respectively. Demographic data, drug toxicity, and clinical, laboratory, and treatment information of different groups were compared.

Results

During the study period, 5086 poisoned patients were hospitalized, of whom 255 (5.1%) had beta-blocker poisoning. Most patients were women (80.8%), married (50.6%), with a history of psychiatric disorders (36.5%), previous suicide attempts (34.6%), and intentional type of exposure (95.3%). The mean ± SD age of the patients was 28.94 ± 11.08 years. Propranolol toxicity was the most common among different beta-blockers (84.4%). There was a significant difference in age, occupation, education level, and history of psychiatric diseases with respect to the type of beta-blocker poisoning (P < 0.05). We observed changes in the consciousness level and need for endotracheal intubation only in the third group (combination of beta-blockers). Only 1 (0.4%) patient had a fatal outcome in toxicity with the combination of beta-blockers.

Conclusion

Beta-blocker poisoning is not common in our poisoning referral center. Propranolol toxicity was most common among different beta-blockers. Although symptoms are not different among defined beta-blocker groups, more severe symptoms are observed in the combination of the beta-blocker group. Only one patient had a fatal outcome in the toxicity with the combination of the beta-blocker group. Therefore, poisoning circumstances have to investigate thoroughly to screen coexposure with combined drugs.

Multiple neurological effects associated with exposure to organophosphorus pesticides in man

This article reviews available data regarding the possible association of organophosphorus (OP) pesticides with neurological disorders such as dementia, attention deficit hyperactivity disorder, neurodevelopment, autism, cognitive development, Parkinson's disease and chronic organophosphate-induced neuropsychiatric disorder. These effects mainly develop after repeated (chronic) human exposure to low doses of OP. In addition, three well defined neurotoxic effects in humans caused by single doses of OP compounds are discussed. Those effects are the cholinergic syndrome, the intermediate syndrome and organophosphate-induced delayed polyneuropathy. Usually, the poisoning can be avoided by an improved administrative control, limited access to OP pesticides, efficient measures of personal protection and education of OP pesticide applicators and medical staff.

Theoretical prediction on the hydrolysis rate of the new types of nerve agents: A density functional study

Although the hydrolysis mechanism of the nerve agents, which is the main decontamination pathway, has been studied experimentally and theoretically, the reliable theoretical prediction method for the hydrolysis rate is not studied yet. Furthermore, after the CWC (Chemical Warfare Agent) list is updated, Novichok candidate structures can be more than 10,000 structures, for which it is not possible to perform the experiment for all of them for synthesizing and getting the hydrolysis rate. Therefore, developing a reliable theoretical method for hydrolysis rate prediction is crucial to prepare for the forthcoming usage of new types of nerve agents. Herein, by using DFT (Density Functional Theory), we successfully developed a new method of predicting the hydrolysis rate on nerve agents by investigating the electrophilicity index (EI) of the various A-, V-, and G-series nerve agents and found a suitable correlation with the experimental hydrolysis rate. Among the several DFT methods, wb97xD predicts the EI with the lowest % deviation of the studied nerve agents. Our results show that EI can be a good indicator to predict the hydrolysis rate of the anticipated nerve agents. Based on the result, we predicted the hydrolysis rate on another type of Novichok candidates, which could be the firm basis for developing a decontaminant and antidote with much fewer experimental efforts on new types of nerve agents.

Selected Political Criminal Poisonings in the Years 1978-2020: Detection and Treatment

Criminal poisonings are among the least frequently detected crimes in the world. Lack of suspicion of this type of event by police officers and prosecutors, clinical symptoms imitating many somatic diseases and technical difficulties in diagnostics, as well as high research costs make the actual frequency of these events difficult to estimate. The substance used for criminal poisoning is often characterized by: lack of taste, color and smell, delayed action, easy availability and difficulty to detect. The aim of the study was to analyze selected cases of political poisoning that took place in the years 1978-2020, to describe the mechanisms of action of the substances used and to evaluate the diagnosis and treatment. The analyzed cases of criminal poisoning concerned: Georgi Markov (ricin), Khalid Maszal (fentanyl), Wiktor Yushchenko (TCDD dioxin), Jasir Arafat (polonium ²¹⁰Po isotope), Alexander Litvinenko (polonium ²¹⁰Po isotope), Kim Jong-Nam (VX), Sergei Skripal (Novichok) and Alexei Navalny (Novichok). Contemporary poisons, to a greater extent than in the past, are based on the use of synthetic substances from the group of organophosphorus compounds and radioactive substances. The possibility of taking appropriate and effective treatment in such cases is the result of many factors, including the possibility of quick and competent rescue intervention, quick and reliable detection of the toxic substance and the possibility of using an antidote.

Are the current commercially available oximes capable of reactivating acetylcholinesterase inhibited by the nerve agents of the A-series?

The misuse of novichok agents in assassination attempts has been reported in the international media since 2018. These relatively new class of neurotoxic agents is claimed to be more toxic than the agents of the G and V series and so far, there is no report yet in literature about potential antidotes against them. To shed some light into this issue, we report here the design and synthesis of NTMGMP, a surrogate of A-242 and also the first surrogate of a novichok agent useful for experimental evaluation of antidotes. Furthermore, the efficiency of the current commercial oximes to reactivate NTMGMP-inhibited acetylcholinesterase (AChE) was evaluated. The Ellman test was used to confirm the complete inhibition of AChE, and to compare the subsequent rates of reactivation in vitro as well as to evaluate aging. In parallel, molecular docking, molecular dynamics and MM-PBSA studies were performed on a computational model of the human AChE (HssAChE)/NTMGMP complex to assess the reactivation performances of the commercial oximes in silico. Experimental and theoretical studies matched the exact hierarchy of efficiency and pointed to trimedoxime as the most promising commercial oxime for reactivation of AChE inhibited by A-242.

Blocking chemical warfare agent simulants by graphene oxide/polymer multilayer membrane based on hydrogen bonding and size sieving effect

Chemical warfare agents (CWAs) are toxic materials that cause death by contact with the skin or by respiration. Although studies on detoxification of CWAs have been intensively conducted, studies that block CWAs permeation are rare. In this study, for blocking CWAs, a multilayer thin film composed of linear polyethylenimine (LPEI) and graphene oxide (GO) is simply prepared through a spray-assisted Layer-by-Layer (LbL) assembly process. LPEI could change its morphology dependent on pH, which is known as a representative hydrogen donor and acceptor. By controlling the shape of the polymer chain, a heterogenous film could have a loose or dense inner structure. CWAs mainly move through diffusion and have hydrogen bonding sites. Therefore, the heterogeneous film can limit CWAs movement based on controlling pathways and hydrogen bonds within the film. The protective effect of this membrane is investigated using dimethyl methylphosphonate (DMMP), a nerve gas simulant. DMMP vapor transmittance rate (DVTR) and N₂ permeance of LPEI/GO are 67.91 g/m² day and 34,293.04 GPU. It means that the protection efficiency is 72.65%. Although this membrane has a thin thickness (100 nm), it shows a high protective effect with good breathability. And water/DMMP selectivity of the membrane is 66.63. Since this multilayer membrane shows efficient protection performance with a simple preparation method, it has a high potential for applications such as protective suits and masks.

Calculation of the infrared spectra of organophosphorus compounds and prediction of new types of nerve agents

IR prediction of Novichok candidates is performed by establishing an accurate DFT calculation method on organophosphorus compounds.

Ultrathin Zirconium Hydroxide Nanosheet-Assembled Nanofibrous Membranes for Rapid Degradation of Chemical Warfare Agents

Organophosphorus-based chemical warfare agents (CWAs) are highly poisonous, and recent attacks using nerve agents have stimulated researchers to develop breakthrough materials for their fast degradation. Zr-based materials have been identified as the most effective catalysts for breaking down CWAs, but in their powdered form, their practical application in personal protective equipment is limited. Herein, a surface-confined strategy for the direct growth of vertically aligned zirconium hydroxide (Zr(OH)₄ ) nanosheets with ultrathin and tortuous structures on nanofibers is reported. The freestanding Zr(OH)₄ nanosheet-assembled nanofibrous membranes (NANMs) show superior catalytic performance to degrade dimethyl methylphosphonate, a nerve agent simulant, with a half-life of 4 min. In addition, intriguing membrane-type NANMs feature integrated properties of exceptional breathability, prominent flexibility, and robust fatigue resistance over one million buckling loads. This facile strategy provides a novel route to manufacture new classes of nanosheet-supported membranes for chemical-protective materials, in particular for gas filters, protective suits, and clothing.

Molecularly imprinted polymers in toxicology: a literature survey for the last 5 years

The science of toxicology dates back almost to the beginning of human history. Toxic chemicals, which are encountered in different forms, are always among the chemicals that should be investigated in criminal field, environmental application, pharmaceutic, and even industry, where many researches have been carried out studies for years. Almost all of not only drugs but also industrial dyes have toxic side and direct effects. Environmental micropollutants accumulate in the tissues of all living things, especially plants, and show short- or long-term toxic symptoms. Chemicals in forensic science can be known by detecting the effect they cause to the body with the similar mechanism. It is clear that the best tracking tool among analysis methods is molecularly printed polymer-based analytical setups. Different polymeric combinations of molecularly imprinted polymers allow further study on detection or extraction using chromatographic and spectroscopic instruments. In particular, methods used in forensic medicine can detect trace amounts of poison or biological residues on the scene. Molecularly imprinted polymers are still in their infancy and have many variables that need to be developed. In this review, we summarized how molecular imprinted polymers and toxicology intersect and what has been done about molecular imprinted polymers in toxicology by looking at the studies conducted in the last 5 years.

Review about Structure and Evaluation of Reactivators of Acetylcholinesterase Inhibited with Neurotoxic Organophosphorus Compounds

BACKGROUND

Neurotoxic chemical warfare agents can be classified as some of the most dangerous chemicals for humanity. The most effective of those agents are the Organophosphates (OPs) capable of restricting the enzyme Acetylcholinesterase (AChE), which in turn, controls the nerve impulse transmission. When AChE is inhibited by OPs, its reactivation can be usually performed through cationic oximes. However, until today, it has not been developed one universal defense agent, with complete effective reactivation activity for AChE inhibited by any of the many types of existing neurotoxic OPs. For this reason, before treating people intoxicated by an OP, it is necessary to determine the neurotoxic compound that was used for contamination, in order to select the most effective oxime. Unfortunately, this task usually requires a relatively long time, raising the possibility of death. Cationic oximes also display a limited capacity of permeating the Blood-Brain Barrier (BBB). This fact compromises their capacity to reactivating AChE inside the nervous system.

METHODS

We performed a comprehensive search on the data about OPs available on the scientific literature today in order to cover all the main drawbacks still faced in the research for the development of effective antidotes against those compounds.

RESULTS

Therefore, this review about neurotoxic OPs and the reactivation of AChE, provides insights for the new agents' development. The most expected defense agent is a molecule without toxicity and effective to reactivate AChE inhibited by all neurotoxic OPs.

CONCLUSION

To develop these new agents, the application of diverse scientific areas of research, especially theoretical procedures as computational science (computer simulation, docking and dynamics), organic synthesis, spectroscopic methodologies, biology, biochemical and biophysical information, medicinal chemistry, pharmacology and toxicology, is necessary.

Recent advances in supramolecular antidotes

Poisons always have fascinated humankind. Initially considered as deleterious or hazardous substances, the modern era has witnessed the controlled utilization of dangerous poisons in medicine and cosmetics. Simultaneously, antidotes have become crucial as reversal agents to counteract the effects of a poison, and they are also used today to positively cancel the benefits of a poison after use. Currently, the majority of poisons are composed of small molecules. This review focuses on recent developments to reverse or prevent toxic effects of poisons by encapsulation in host molecules. Cyclodextrins, cucurbiturils, acyclic cucurbituril derivatives, calixarenes, and pillararenes, have been reported to largely impact the effects of toxic compounds, thus extending the current paradigm of small molecule antidotes by adding a new family of macrocyclic compounds to the current arsenal of antidotes. Along this line of research, endogenous "harmful" species are also sequestered by one or more of these supramolecular host molecules, expanding the potential of supramolecular antidotes to diverse therapeutic areas.

Venoms and poisonings during the centuries. A narrative review

Suffice it to say that the first traces of its use by man date back to ten thousand years ago the venom or poison since the last period of the Paleolithic man used poison to hunt and for defence. Indeed, in the second half of the 19th century, was found in some caves arrows made from the bones of animals characterized by particular grooves. In ancient Greece, the term pharmakon (φάρμακον) had a double meaning: remedy for therapy and venom. This is the period in which we become aware of the fact that a poison cannot be defined only as a substance capable of changing the properties of things. The poisonings are very frequent in the history of the Roman Empire and later in the Renaissance and the modern era. Poison was the protagonist political intrigues of power and is one of the most used lethal weapons over the years. Optimal solution for a perfect murder, the poison has a long history. Its success is due to the invisible and often unpunished death.

Challenges in Fluorescence Detection of Chemical Warfare Agent Vapors Using Solid-State Films

Organophosphorus (OP)-based nerve agents are extremely toxic and potent acetylcholinesterase inhibitors and recent attacks involving nerve agents highlight the need for fast detection and intervention. Fluorescence-based detection, where the sensing material undergoes a chemical reaction with the agent causing a measurable change in the luminescence, is one method for sensing and identifying nerve agents. Most studies use the simulants diethylchlorophosphate and di-iso-propylfluorophosphate to evaluate the performance of sensors due to their reduced toxicity relative to OP nerve agents. While detection of nerve agent simulants in solution is relatively widely reported, there are fewer reports on vapor detection using solid-state sensors. Herein, progress in organic semiconductor sensing materials developed for solid-state detection of OP-based nerve agent vapors is reviewed. The effect of acid impurities arising from the hydrolysis of simulants and nerve agents on the efficacy and selectivity of the reported sensing materials is also discussed. Indeed, in some cases it is unclear whether it is the simulant that is detected or the acid hydrolysis products. Finally, it is highlighted that while analyte diffusion into the sensing film is critical in the design of fast, responsive sensing systems, it is an area that is currently not well studied.

Acetylcholinesterase: The "Hub" for Neurodegenerative Diseases and Chemical Weapons Convention

This article describes acetylcholinesterase (AChE), an enzyme involved in parasympathetic neurotransmission, its activity, and how its inhibition can be pharmacologically useful for treating dementia, caused by Alzheimer's disease, or as a warfare method due to the action of nerve agents. The chemical concepts related to the irreversible inhibition of AChE, its reactivation, and aging are discussed, along with a relationship to the current international legislation on chemical weapons.

Novichoks: The Dangerous Fourth Generation of Chemical Weapons

“Novichoks” is the name given to the controversial chemical weapons supposedly developed in the former Soviet Union between the 1970s and the 1990s. Designed to be undetectable and untreatable, these chemicals became the most toxic of the nerve agents, being very attractive for both terrorist and chemical warfare purposes. However, very little information is available in the literature, and the Russian government did not acknowledge their development. The intent of this review is to provide the IJMS readers with a general overview on what is known about novichoks today. We briefly tell the story of the secret development of these agents, and discuss their synthesis, toxicity, physical-chemical properties, and possible ways of treatment and neutralization. In addition, we also wish to call the attention of the scientific community to the great risks still represented by nerve agents worldwide, and the need to keep constant investments in the development of antidotes and ways to protect against such deadly compounds.

Theoretical study of the molecular aspect of the suspected novichok agent A234 of the Skripal poisoning

Novichoks are the suspected nerve agents in the March 2018 Skripal poisoning. In this context, the novichok agent A234 (chemical structure proposed by Mirzayanov) was studied using computational methods to shed light on its molecular, electronic, spectroscopic, thermodynamic and toxicity parameters as well as on potential thermal and hydrolysis degradation pathways. The poisoning action and antidote of A234 were also investigated. Some of these parameters were compared to three common G- and V-series nerve agents, namely GB, VR and VX. The research findings should be useful towards the detection, development of antidotes and destruction of A234.

Chemical warfare agent NOVICHOK - mini-review of available data

The Cold War period is characterized by the infighting between the Western countries and the USSR in diverse areas. One of such fields was development of the weapons of mass destruction. Within various programs on both sides, a wide scale of different agents have been developed. However, information about some of them are still protected under the designation "top secret". Notwithstanding, in history several cases are known when such information beheld the daylight. One of such cases was the program FOLIANT and NOVICHOK. Both programs were developed by the USSR as a reaction to English/American invention of VX agent. If at least a part of available information is truthful, we can allege that these compounds belong among the most toxic synthetic agents ever. Within this contribution, we have reviewed available Eastern and Western data about the A-agents and their precursors, so-called NOVICHOKs, including their history, synthesis, physical-chemical properties, pharmacological characteristics and clinical manifestation.