Neurotoxicity Of Pesticides

Author by : Michael Aschner
Languange : en
Publisher by : Academic Press
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Description : Neurotoxicity of Pesticides, Volume Four, in this comprehensive serial addresses contemporary advances in neurotoxicology of pesticides by providing authoritative review articles on key issues in the field. Edited by leading subject experts, topics of note in this new release include Organophosphates, OPs, Nerve agents, Pyrethroids, Neonicotinoids and Formamidines, among others.


Neurotoxicity Of Pesticides To Salmon

Author by : Keith Bryan Tierney
Languange : en
Publisher by : Unknown
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Description : Pesticides routinely found in the environment can adversely affect neurological systems of salmon. The major focus of the studies presented here is on the impairment of the relatively exposed olfactory sensory neurons (OSNs), since their functionality is critical to several indispensable behaviours. The responses of OSNs to various behaviourally-relevant odorants were impaired following exposure to several pesticide classes, including triazine (e.g. atrazine), carbamate (e.g. IPBC), organophosphorus (e.g. dimethoate), and phenylurea (e.g. linuron) pesticides, as well as a pesticide formulation (i.e. Roundup). In many cases, within minutes of exposure to environmentally realistic (part per billion) concentrations, impairments of greater than 50% in OSN responses were noted. Pesticides can selectively affect different OSN classes, since one pesticide (linuron) negatively affected amino acid but not bile salt responses. Lengthy (four-day) exposure to a mixture of pesticides modelled after that found in the Nicomekl River (British Columbia) also reduced OSN responses, confirming that pesticide mixtures found in salmon-producing waterways may be injurious. In fact, the ability to discern a change in odorant intensity was reduced by 25%. This may have partially been due to inadequate neuroprotection, as glutathione-S-transferase, an enzyme that protects against cellular damage, was not upregulated to any greater of an extent than it was in fish given a 10-fold lower exposure concentration. To relate changes in OSN responses to behavioural responses, experiments were conducted on two olfactory-mediated behaviours: an amino acid-evoked searching behaviour, and an anti-predator alarm response. In the first case, exposure to three different pesticides disproportionately impacted searching behaviour with respect to neurological impairment, as the searching response was completely eliminated at greater than 60% impairment of neurological response. In the second case, the freezing behaviour salmon perform after detecting harm in a conspecific was progressively reduced with exposure to increasing concentrations of a carbamate. The work here endeavoured to assess how pesticides affect salmon neurophysiology, then relate the effects to altered behaviours, and finally place the findings within a context of environmental realism, regulations, and the status of salmon within Canada and the world.


Pesticides Neurotoxic Illnesses And The Law

Author by : Ann V. Kuczerpa
Languange : en
Publisher by : Lulu Press, Inc
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Description : Every man who by his culpable negligence causes the death of another, although without intent to kill, is guilty of manslaughter. So highly does the law value human life, that it admits no justification wherever a life has been lost, and the carelessness or negligence of one person contributed to the death of another. Regina v. Swindall, 2 Car. & Kir. 222, 233.


Pesticide And Venom Neurotoxicity

Author by : D. Shankland
Languange : en
Publisher by : Springer
Format Available : PDF, ePub, Mobi
Total Read : 38
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Description : The development of the modern organic insecticides has contri buted a major chapter to the history of neurotoxicants. From their roots in the organochlorines and organophosphates discovered prior to and during the Second World War, to the carbamates developed in the 1950's, and most recently to the extremely potent and promising synthetic pyrethroids, the most important organic insecticides have been those whose wite of action lies within the nervous system. In this regard, man is only mimicking nature in attacking the nervous system with lethal intent since potent neurotoxins are cornmon compo nents of the venoms with which animals of all types defend themselves and subdue their prey. This central role of the nervous sytem as a broad target for pesticides may also be projected into the future - a prediction to which this volume is devoted. The nervous system in its diversity is likely to be of central concern to those charged with discovering novel pesticides whether they be modifications of familiar chemical groups or structurally novel neurotoxicants such as the nitromethyl ene insecticides described here. On a second front, the ability to influence insect behavior through the nervous system will become increasingly important in pest management. Pheromones represent one obvious example of this; recent work described in this volume indi cates that the forrnamidine pesticides may represent another.


Pesticide Induced Delayed Neurotoxicity

Author by : United States. Environmental Protection Agency
Languange : en
Publisher by : Unknown
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Anticholinesterase Pesticides

Author by : Tetsuo Satoh
Languange : en
Publisher by : John Wiley & Sons
Format Available : PDF, ePub, Mobi
Total Read : 97
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Description : This book offers an important reference source about the most common classes of pesticides for researchers engaged in the area of neurotoxicology, metabolism, and epidemiology. The book presents details about thorough characterization of target and non-target enzymes and proteins involved in toxicity and metabolism; and epidemiology of poisonings and fatalities in people from short- and long- term exposures to these pesticides in different occupational settings on an individual country basis as well as on a global basis. The early portion of the book deals with metabolism, mechanisms and biomonitoring of anticholinesterase pesticides, while the later part deals with epidemiological studies, regulatory issues, and therapeutic intervention.


Pesticide Neurotoxicity

Author by : Kristina L. Brown
Languange : en
Publisher by : Unknown
Format Available : PDF, ePub, Mobi
Total Read : 59
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Handbook Of Neurotoxicology

Author by : Edward J. Massaro
Languange : en
Publisher by : Springer Science & Business Media
Format Available : PDF, ePub, Mobi
Total Read : 72
Total Download : 496
File Size : 46,8 Mb
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Description : Neurotoxicology is a broad and burgeoning field of research. Its growth in recent years can be related, in part, to increased interest in and concern with the fact that a growing number of anthropogenic agents with neurotoxic potential, including pesticides, lead, mercury, and the polytypic bypro ducts of combustion and industrial production, continue to be spewed into and accumulate in the environment. In addition, there is great interest in natural products, including toxins, as sources of therapeutic agents. Indeed, it is well known that many natural toxins of broadly differing structure, produced or accumulated for predatory or defensive purposes, and toxic agents, accumulated incidentally by numerous species, function to perturb nervous tissue. Components of some of these toxins have been shown to be useful therapeutic agents and/or research reagents. Unfor tunately, the environmental accumulation of some neurotoxic ants of anthropogenic ori gin, especially pesticides and metals, has resulted in incidents of human poisoning, some of epidemic proportion, and high levels of morbidity and mortality. Furthermore, an increasing incidence of neurobehavioral disorders, some with baffling symptoms, is confronting clinicians. It is not clear whether this is merely the result of increased vigi lance and/or improved diagnostics or a consequence of improved health care. In any case, the role of exposure to environmental and occupational neurotoxic ants in the etiology of these phenomena, as well as neurodegenerative diseases, is coming under increasing scrutiny and investigation.


Endosulfan Neurotoxicity

Author by : Habiba Bano
Languange : en
Publisher by : LAP Lambert Academic Publishing
Format Available : PDF, ePub, Mobi
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Description : To enhance crop production heavy tonnage of pesticides is being used around the globe. Endosulfan, is one such organochlorine pesticide that had been is usage from a long time. It possess severe health impacts and also cause damage to the central nervous system.Antioxidants such as resveratrol on the other hand, acts to counterbalance the toxic effects of pesticides. This study was designed to evaluate the ameliorative potential of resveratrol against endosulfan induced neurotoxicity. For this different nuclei and fibre tracts of various regions of the mice brain have been mapped using histochemical localization of the neurotransmitter enzyme ATPase.


Toxicology Of Organophosphate And Carbamate Compounds

Author by : Ramesh C. Gupta
Languange : en
Publisher by : Academic Press
Format Available : PDF, ePub, Mobi
Total Read : 67
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Description : This text/reference book provides the most comprehensive coverage of anticholinesterase compounds (Organophosphates and Carbamates), which constitute the largest number of chemicals that are primarily used as insecticides in agriculture, industry, and around the home/garden. Some OPs (nerve agents) have been used in chemical warfare and terrorist attacks, while some OPs and CMs have been recommended as therapeutic agents in human medicine as well as in veterinary medicine. Many chemicals of both classes are extremely toxic and lack selectivity, thus their inadvertent/accidental use continues to pose a threat to human and animal health, aquatic systems and wildlife. These anticholinesterase agents produce a variety of toxicological effects in target and nontarget organs. In light of this complexicity, this multi-authored book is written by the well known scientists from many countries. The book is organized into nine sections, with a total of 49 chapters, to provide in-depth knowledge on various aspects of OP and CM compounds, including their use, classification, mechanism-based toxicity, and prophylactic and therapeutic measurements. Several chapters are written with special emphasis to cover timely topics, such as chemical warfare agents, physiologically-based pharmacokinetic modeling, structure and function of cholinesterases, paraoxonase, carboxylesterases; developmental neurotoxicity, the intermediate syndrome, oxidative stress, endocrine disruption, and DNA damage/gene expression and carcinogenesis. Section-VI with 5 chapters is specifically devoted to risk assessment, and safety and regulatory guidelines for pesticides. Describes everything you need to know about Organophosphates and Carbamates Extensively covers pesticides, nerve agents, therapeutic drugs, and flame retardants Describes epidemiology of the world's major disasters involving Organophosphates and Carbamates Covers animal, human, aquatic, and wildlife toxicity of Anticholinesterases Insights into in-depth cholinergic and noncholinergic mechanisms of toxicity Describes recent advancements in cholinesterases, paraoxonases, carboxylesterases, oxidative stress, endocrine disruption, cardiac and pulmonary toxicity, and carcinogenesis Provides in vitro and in vivo models for neurotoxicity testing Integrates knowledge of studies in lab animals and humans Offers risk/safety assessment and national/international guidelines for permissible levels of pesticide residues Describes management of Anticholinesterase poisoning in humans


Pesticides And Neurological Diseases

Author by : Donald J. Ecobichon
Languange : en
Publisher by : CRC Press
Format Available : PDF, ePub, Mobi
Total Read : 19
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Description : Since the publication of the original edition in 1982, pesticide-related poisonings, both single cases and epidemic-scale situations, have continued to occur unabated. This new edition of Pesticides and Neurological Diseases reviews current literature describing the effects of insecticides (chlorinated hydrocarbons, organophosphorus and carbamate e


Neurotoxicity

Author by : United States. Congress. Office of Technology Assessment
Languange : en
Publisher by : Unknown
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Description :


Enzyme Based Detoxification Of Organophosphorus Neurotoxic Pesticides And Chemical Warfare Agents

Author by : Rory James Kern
Languange : en
Publisher by : Unknown
Format Available : PDF, ePub, Mobi
Total Read : 94
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Description : There are some 15,000 known organophosphorus chemicals. Some of these OP's, including VX and paraoxon, demonstrate an acute neurotoxicity due to the inhibition of cholinergic enzymes. Organophosphorus chemical warfare agents and pesticide neurotoxins are subject to hydrolysis by OP degrading enzymes. To be useful as a bioremediation or anti-chemical warfare agent, the enzyme must be tailored for, and integrated into, a practical application platform. Several studies have established enzyme-based countermeasures, describing such diverse applications as decontaminating foams for surface remediation, encapsulating enzyme with liposome for in vivo therapy, enzyme attachments to surfaces for biosensors and development of a corn expression system for large-scale enzyme production. The goal of the research described here is to select, investigate and improve the operational potential of organophosphate-degrading enzymes including Organophosphorus Hydrolase (OPH, 3.1.8.1) and Organophosphorus Acid Anhydrolase (OPAA, 3.1.8.2). Using saturation kinetics, the catalytic efficiencies of these two major detoxification enzymes were characterized with substrates representing each class of OP neurotoxin, phosphotriester, phosphothioate and phosphofluoridate. OPH presents superior kinetic parameters with each OP class tested. Variants of OPH were created to increase the operational effectiveness of OP hydrolytic enzymes against phosphorothioates. An H254S/H257L mutation in the active site resulted in an improvement in the kinetics (kcat/KM) for the phosphorothioate, demeton-S. To screen potential vascular protection therapies, an in vitro protocol was developed to predict enzymatic effectiveness for protection of acetylcholinesterase from acute OP-inhibition. The protection abilities of the enzymes were directly related to their second order rate constants as inhibitory levels of OP are below the KM of the enzymes. Consideration of contaminant nature concentration and enzyme kinetic parameters, kcat and KM, is critical to understanding decontamination and effective use of enzyme technology. These technologies continue to develop and provide promising new decontamination tools for OP compounds.


Reactive Dopamine Metabolites And Neurotoxicity

Author by : Brigitte Chantal Vanle
Languange : en
Publisher by : Unknown
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Description : This benzimidazole fungicide, benomyl was shown to inhibit ALDH2 in the SH-SY5Y neuroblastoma cell line via an increase in DOPAL and a decrease in DOPAC. The ratios of DOPAL and DOPAC, the product of ALDH, were measured by HPLC-ECD, and found that benomyl does inhibit ALDH2 in this dopaminergic cell model. The cytotoxicity of benomyl, DA, DOPAL and the combination of DA or DOPAL with benomyl was assessed by MTT assay. Surprisingly, the only toxic combination was the combination of DA or DOPAL with benomyl. In fact, this toxicity appears to be synergistic, as none of the single treatments are significantly toxic to the cells. This synergistic effect also affects GAPDH aggregation. The cell morphology is also drastically different in the presence of the combined treatments, compared to individual treatment of DA, DOPAL or benomyl; cells start to ebb and show apoptotic-like features at just 2h. A second class of pesticides, named chlorpyrifos and chlorpyrifos-oxon were tested for toxicity in PC6-3These compounds were toxic to these cells due to DOPAL accumulation reaching high levels in the 100 μM range. Exposure to environmental toxins such as pesticides and fungicides has long been linked to PD risk, but only recently to DOPAL levels. This work provides a novel mechanism by which fungicide exposure may stimulate PD pathogenesis.


Neurotoxicity Of The Parkinson S Disease Associated Pesticide Ziram Is Synuclein Dependent

Author by : Aaron Lulla
Languange : en
Publisher by : Unknown
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Description : Parkinson's disease (PD) is the second most common neurodegenerative disease, affecting seven to ten million people worldwide. Familial forms of PD account for 5-10% of all PD cases suggesting that other factors such as the environment have a role in the development of sporadic cases of PD. Epidemiological studies have indicated that exposure to pesticides increases the risk for PD. Ziram, a dithiocarbamate fungicide commonly used in California, increases the risk of PD for individuals living and working in areas where the pesticide is sprayed. Ziram has previously been found in vitro to cause selective dopaminergic cell toxicity, inhibition of the ubiquitin proteasome system (UPS), and increased -synuclein ( -syn) levels in primary neuronal cultures. In this dissertation we utilize zebrafish embryos (ZF, Danio rerio) to study ziram in an in vivo system and to determine if ziram's toxicity is mediated via synuclein. We found that ziram is toxic to ZF at nanomolar concentrations and caused selective loss of dopaminergic (DA) neurons and impaired swimming behavior in ZF. Since ziram increases -syn concentrations in rat primary neuronal cultures, we investigated the effect of ziram on ZF -synuclein 1 ( 1). ZF express 3 synuclein isoforms and ZF 1 appears to be a functional homologue of -syn. We found that recombinant ZF 1 formed fibrils in vitro and overexpression of ZF 1 in ZF embryos led to the formation of neuronal aggregates and neurotoxicity similarly to -syn. Importantly, knockdown of ZF 1 with morpholinos or disruption of oligomers with the molecular tweezer CLR01 protected against ziram's DA toxicity. Over the course of this dissertation we have demonstrated that ziram is selectively toxic to DA neurons in vivo and that its toxicity is synuclein-dependent. These findings provide potentially important mechanistic implications on how ziram and possibly other environmental toxins can contribute to the pathogenesis of neurodegenerative disorders such as PD.


Intolerable Risk

Author by : Bradford H. Sewell
Languange : en
Publisher by : Unknown
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Description : Abstract: This report presents a detailed analysis of children's exposure to pesticides in food and a determination of the potential hazards that these residues pose to children. Preschoolers' exposure to 23 pesticides was determined by combining children's consumption rates for various foods with the actual pesticide residue levels found in these foods. Pesticide exposure estimates were then assessed to determine the preschoolers' risk of developing cancer or experiencing a disruoption in central nervous system function. The study concluded that preschoolers are being exposed to hazardous levels of pesticides in fruits and vegetables.


The Effects Of Pesticides On Human Health

Author by : Scott R. Baker
Languange : en
Publisher by : Princeton Scientific Pub
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Description : Pesticides are developed specifically for their ability to interact & interfere with a variety of biological targets. Because of the fundamental similarities of organisms at the subcellular level, selectivity is often difficult to achieve & unanticipated pesticide actions leading to a number of adverse health effects may result. Some occupational exposure to pesticides is unavoidable, even with strict adherence to good agricultural practices & proper application procedures. This book, presenting the results of a 1988 workshop focusing on the potential chronic health effects of pesticides, addresses the topics of pesticide exposure, neurotoxicity, carcinogenicity, immunotoxicity, developmental toxicity, & reproductive toxicity. Pesticides discussed include: organochlorine insecticides, DDT & its derivatives, hexachlorocyclohexanes & cyclodienes, chlordecone, anticholinesterase insecticides, organophosphorus esters, carbamates, pyrethrins & pyrethroid insecticides, & herbicides, fungicides, & fumigants. A valuable source of information for biological chemists, toxicologists, pathologists, pharmacists, regulatory officials, environmentalists, governmental & state scientists, attorneys, managers, & biomedical scientists.


Organophosphates Chemistry Fate And Effects

Author by : Janice E. Chambers
Languange : en
Publisher by : Elsevier
Format Available : PDF, ePub, Mobi
Total Read : 94
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Description : This volume pulls together a wealth of up-to-date information on the toxicology of this diverse and ubiquitous class of insecticides. Leading experts review the reactivity of organophosphorus compounds with cholinesterase, as well as their metabolism and biological effects on humans and other nontarget organisms. The book not only covers the anticholinesterase actions of organophosphates, but also other, presumably independent, effects, such as teratogenicity, delayed neuropathy, immunotoxicity, and behavioral toxicity. Offers crucial overviews of chemical and biochemical reactivity and biological responsiveness of mainly nontarget organisms Reviews new developments in assessment of metabolism and disposition of organophosphorus compounds Examines organophosphorus compound-induced toxicity mediated by mechanisms other than inhibition of acetylcholinesterase Covers new research on differences in toxicity induced by the variety of organophosphorus Analyzes current controversies on the relevance of certain biochemical parameters in actual organophosphate toxicity in vivo


Pesticides Man And Biosphere

Author by : O. P. Shukla
Languange : en
Publisher by : APH Publishing
Format Available : PDF, ePub, Mobi
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Description :


Handbook Of Neurotoxicology

Author by : Edward J. Massaro
Languange : en
Publisher by : Humana
Format Available : PDF, ePub, Mobi
Total Read : 19
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Description : Neurotoxicology is a broad and burgeoning field of research. Its growth in recent years can be related, in part, to increased interest in and concern with the fact that a growing number of anthropogenic agents with neurotoxic potential, including pesticides, lead, mercury, and the polytypic bypro ducts of combustion and industrial production, continue to be spewed into and accumulate in the environment. In addition, there is great interest in natural products, including toxins, as sources of therapeutic agents. Indeed, it is well known that many natural toxins of broadly differing structure, produced or accumulated for predatory or defensive purposes, and toxic agents, accumulated incidentally by numerous species, function to perturb nervous tissue. Components of some of these toxins have been shown to be useful therapeutic agents and/or research reagents. Unfor tunately, the environmental accumulation of some neurotoxic ants of anthropogenic ori gin, especially pesticides and metals, has resulted in incidents of human poisoning, some of epidemic proportion, and high levels of morbidity and mortality. Furthermore, an increasing incidence of neurobehavioral disorders, some with baffling symptoms, is confronting clinicians. It is not clear whether this is merely the result of increased vigi lance and/or improved diagnostics or a consequence of improved health care. In any case, the role of exposure to environmental and occupational neurotoxic ants in the etiology of these phenomena, as well as neurodegenerative diseases, is coming under increasing scrutiny and investigation.


The Neurotoxicity Of Inhaled Paraquat A Translationally Relevant Route Of Exposure

Author by : Timothy J. Anderson
Languange : en
Publisher by : Unknown
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Description : Numerous epidemiological studies have reported associations between the broad spectrum herbicide paraquat (PQ) and Parkinson's disease (PD), with findings supported by injection and feeding studies. Despite evidence that inhalation exposure to airborne pesticides, such as PQ, is an occupational and public health concern, the ability of inhaled PQ to reproduce features of PD has not been investigated. The present study was designed to determine if inhalation exposure to PQ would lead to its disposition to the brain, dopaminergic dysregulation, and neurobehavioral outcomes consistent with the trajectory of PD. Adult male and female C57BL/6J mice were exposed to PQ aerosols (130 æg/m3) in a whole-body inhalation chamber for 4hrs/day, 5 days/week for 4 weeks. Subsets of males were sacrificed during and after exposure and PQ concentrations in various brain regions (olfactory bulb, striatum, midbrain, and cerebellum) were quantified via mass spectrometry. Alterations in motor behavior were examined using spontaneous locomotor activity, rota-rod, and grip strength. Following the conclusion of behavioral assessment 275 days after the end of exposure, mice were sacrificed and neurotransmitters were measured by mass spectrometry. PQ inhalation resulted in significant concentrations in all examined brain regions, with the highest burden observed in the olfactory bulb, consistent with nasal olfactory translocation. PQ led to significant male-specific deficits in olfactory discrimination. PQ inhalation also produced male- specific deficits in locomotor activity and grip strength, but no significant effect on motor coordination on the rota-rod apparatus. Critically, PQ inhalation exposure led to a significant male-specific reduction in midbrain dopamine, even 275 days post-exposure. Further, in the striatum, PQ significantly reduced the dopamine metabolite, homovanillic acid, glutamine, serotonin, and its metabolite 5-HIAA, relative to filtered-air controls. These data highlight the importance of inhalation as route of exposure for neurotoxic pesticides in the airborne state and lend biological plausibility to a causal relation between PQ and PD. These effects are sex-specific, and future research is needed to identify mechanisms of sex-differentiated toxicity.


Handbook Of Neurotoxicology

Author by : Edward J. Massaro
Languange : en
Publisher by : Springer Science & Business Media
Format Available : PDF, ePub, Mobi
Total Read : 66
Total Download : 640
File Size : 51,9 Mb
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Description : N eurotoxicology is a broad and burgeoning field of research. Its growth in recent years can be related, in part, to increased interest in and concern with the fact that a growing number of anthropogenic agents with neurotoxic potential, including pesticides, 1ead, mercury, and the polytypic byproducts of combustion and industrial production, continue to be spewed into and accumulate in the environment. In addition, there is great interest in natural products, including toxins, as sources of therapeutic agents. Indeed, it is well known that many natural toxins ofbroadly differing structure, produced or accumulated for predatory or defensive purposes, and toxic agents, accumulated incidentalIy by numerous species, function to perturb nervous tissue. Components of some of these toxins have been shown to be useful therapeutic agents and/or research reagents. Unfor of some neurotoxicants of anthropogenic ori tunately, the environmental accumulation gin, expecialIy pesticides and metals, has resulted in incidents ofhuman poisoning, some of epidemic proportion, and high levels of morbidity and mortality. Furthermore, an increasing incidence of neurobehavioral disorders, some with baffling symptoms, is confronting clinicians. It is not clear whether this is merely the re suit of increased vigi lance and/or improved diagnostics or a consequence of improved health care. In any case, the role of exposure to environmental and occupational neurotoxicants in the etiology of these phenomena, as well as neurodegenerative diseases, is coming under increasing scrutiny and investigation.