Toxinology
Encyclopedia
Toxinology is the specialized area of science
Science
Science is a systematic enterprise that builds and organizes knowledge in the form of testable explanations and predictions about the universe...

 that deals specifically with animal, plant, and microbial toxins
Microbial toxins
Microbial toxins are toxins produced by microorganisms, including bacteria, viruses and fungi. Microbial toxins are important virulence determinants responsible for microbial pathogenicity and/or evasion of the host immune response. Some bacterial toxins, such as Botulinum neurotoxins, are the most...

. Prof. Dietrich Mebs has defined toxinology as "the scientific discipline dealing with microbial, plant and animal venom
Venom
Venom is the general term referring to any variety of toxins used by certain types of animals that inject it into their victims by the means of a bite or a sting...

s, poison
Poison
In the context of biology, poisons are substances that can cause disturbances to organisms, usually by chemical reaction or other activity on the molecular scale, when a sufficient quantity is absorbed by an organism....

s and toxin
Toxin
A toxin is a poisonous substance produced within living cells or organisms; man-made substances created by artificial processes are thus excluded...

s". Additionally stating that "toxinology includes more than just the chemistry
Chemistry
Chemistry is the science of matter, especially its chemical reactions, but also its composition, structure and properties. Chemistry is concerned with atoms and their interactions with other atoms, and particularly with the properties of chemical bonds....

 and mode of action
Mode of action
Historically, pesticides have often been classified according to their chemical groups and this is useful for understanding the properties of a given compound. However, it is the Mode of Action group which possibly represents the most useful pesticide classification for biologists...

 of a toxin. It deals also with the biology of venom- or poison-producing organism, the structure and function of the venom apparatus, as well as the use of the venom or poison, the ecological role of these compounds." Prof. Jurg Meier has defined toxinology as "the science of toxic substances produced by or accumulated in living organisms, their properties, and their biological significance for the organisms involved".

There is an International Society on Toxinology (IST), founded in 1962, catering for toxinologists and their research, with an international Congress every three years and regional sectional meetings in intervening years. The IST has, or is in the process of adopting several key initiatives, notably regularising toxin nomenclature
Nomenclature
Nomenclature is a term that applies to either a list of names or terms, or to the system of principles, procedures and terms related to naming - which is the assigning of a word or phrase to a particular object or property...

 (through work of an expert committee), developing the field of clinical toxinology as a global training
Training
The term training refers to the acquisition of knowledge, skills, and competencies as a result of the teaching of vocational or practical skills and knowledge that relate to specific useful competencies. It forms the core of apprenticeships and provides the backbone of content at institutes of...

 and accreditation
Accreditation
Accreditation is a process in which certification of competency, authority, or credibility is presented.Organizations that issue credentials or certify third parties against official standards are themselves formally accredited by accreditation bodies ; hence they are sometimes known as "accredited...

 initiative, and supporting efforts to reduce the global toll from snakebite
Snakebite
A snakebite is an injury caused by a bite from a snake, often resulting in puncture wounds inflicted by the animal's fangs and sometimes resulting in envenomation. Although the majority of snake species are non-venomous and typically kill their prey with constriction rather than venom, venomous...

, through the Global Snakebite Initiative. Details of these and other activities, including a Society electronic newsletter
Newsletter
A newsletter is a regularly distributed publication generally about one main topic that is of interest to its subscribers. Newspapers and leaflets are types of newsletters. Additionally, newsletters delivered electronically via email have gained rapid acceptance for the same reasons email in...

 are available via the Society web site at www.toxinology.org. The society also has an official journal, Toxicon
Toxicon
Toxicon is a peer-reviewed scientific journal of toxinology, and the official journal of the International Society on Toxinology. It is published by Elsevier and is edited by Alan L. Harvey...

. A number of countries have established national toxinology societies and these hold national meetings. There are several journals, besides Toxicon, than principally cover toxin research and major discoveries in toxinology can be published in a wide variety of journals, including Nature
Nature (journal)
Nature, first published on 4 November 1869, is ranked the world's most cited interdisciplinary scientific journal by the Science Edition of the 2010 Journal Citation Reports...

.

Toxins and toxinology

Toxins are natural substances, or substances produced by living organisms, in contrast to toxic substances from chemicals, which are toxicant
Toxicant
A toxicant is a chemical compound that has an effect on organisms.A distinction can be drawn between "toxic" and toxin, with the latter being a subcategory of the former....

s. Living organisms producing or using toxins do so as either venoms or poisons. Venoms are toxins, or more commonly, collections of varying toxins, that are used actively against prey or predators, most commonly to subdue, kill and digest prey, or dissuade predators. Poisons of natural origin, that is containing toxins and used by living organisms, are passive and generally used for defence. A predator attempting to molest or eat a poisonous animal
Animal
Animals are a major group of multicellular, eukaryotic organisms of the kingdom Animalia or Metazoa. Their body plan eventually becomes fixed as they develop, although some undergo a process of metamorphosis later on in their life. Most animals are motile, meaning they can move spontaneously and...

, plant
Plant
Plants are living organisms belonging to the kingdom Plantae. Precise definitions of the kingdom vary, but as the term is used here, plants include familiar organisms such as trees, flowers, herbs, bushes, grasses, vines, ferns, mosses, and green algae. The group is also called green plants or...

 or mushroom
Mushroom
A mushroom is the fleshy, spore-bearing fruiting body of a fungus, typically produced above ground on soil or on its food source. The standard for the name "mushroom" is the cultivated white button mushroom, Agaricus bisporus; hence the word "mushroom" is most often applied to those fungi that...

 will suffer adverse effects from the toxins in the poison, varying from mild discomfort to rapid death. Particularly food poisons, but also for a few venoms, the component toxins are not produced by the deploying animal/plant, but are made by micro-organisms and concentrated and used by the deploying animal/plant. A good example is tetrodotoxin
Tetrodotoxin
Tetrodotoxin, also known as "tetrodox" and frequently abbreviated as TTX, sometimes colloquially referred to as "zombie powder" by those who practice Vodou, is a potent neurotoxin with no known antidote. There have been successful tests of a possible antidote in mice, but further tests must be...

, used by a variety of poisonous animals and by a few venomous animals.

Toxins and toxinology is not solely focussed on adverse effects. An increasing number of toxins are important as research tools, unlocking secrets of disease
Disease
A disease is an abnormal condition affecting the body of an organism. It is often construed to be a medical condition associated with specific symptoms and signs. It may be caused by external factors, such as infectious disease, or it may be caused by internal dysfunctions, such as autoimmune...

, or as diagnostic agents in hospital laboratories, or as therapeutic agents to treat human disease, including anti-cancer agents, anti-epileptic agents, anti-clotting agents, analgesic
Analgesic
An analgesic is any member of the group of drugs used to relieve pain . The word analgesic derives from Greek an- and algos ....

s, anti-hypertensive drugs, to name but a few. This is a very rich field for research.

Venomous animals can be found in a number of Phyla
Phylum
In biology, a phylum The term was coined by Georges Cuvier from Greek φῦλον phylon, "race, stock," related to φυλή phyle, "tribe, clan." is a taxonomic rank below kingdom and above class. "Phylum" is equivalent to the botanical term division....

. Some prominent examples include: Phylum Chordata, Subphylum
Subphylum
In life, a subphylum is a taxonomic rank intermediate between phylum and superclass. The rank of subdivision in plants and fungi is equivalent to subphylum.Not all phyla are divided into subphyla...

 Vertebrata - venomous snake
Venomous snake
"Poisonous snake" redirects here. For true poisonous snakes, see Rhabdophis.Venomous snakes are snakes which have venom glands and specialized teeth for the injection of venom...

s (approximately 800 species in Families Viperidae
Viperidae
The Viperidae are a family of venomous snakes found all over the world, except in Antarctica, Australia, Ireland, Madagascar, Hawaii, various other isolated islands, and above the Arctic Circle. All have relatively long, hinged fangs that permit deep penetration and injection of venom. Four...

, Elapidae
Elapidae
Elapidae is a family of venomous snakes found in tropical and subtropical regions around the world, terrestrially in Asia, Australia, Africa, North America and South America and aquatically in the Pacific and Indian Oceans...

, Atractaspididae
Atractaspididae
The Atractaspididae are a family of snakes found in Africa and the Middle East. Currently, 12 genera are recognized.-Description:This family includes many genera formerly classed in other families, on the basis of fang type. It includes fangless , rear-fanged , fixed-fanged , and viper-like species...

 and Colubridae* (* this family is an artificial construct and will likely be broken up into a variety of new families)), venomous lizards (two species from the Americas
Americas
The Americas, or America , are lands in the Western hemisphere, also known as the New World. In English, the plural form the Americas is often used to refer to the landmasses of North America and South America with their associated islands and regions, while the singular form America is primarily...

 - Heloderma horridum and H. suspectum; also recent controversial research has claimed some other lizards can produce toxins, notably varanid lizards), venomous mammals
Venomous mammals
Venomous mammals are animals of the class Mammalia that produce venom, which they use to kill or disable prey, or to defend themselves from predators. In modern nature, venomous mammals are quite rare. Venom is much more common among other vertebrates; there are many more species of venomous...

 (notably the platypus
Platypus
The platypus is a semi-aquatic mammal endemic to eastern Australia, including Tasmania. Together with the four species of echidna, it is one of the five extant species of monotremes, the only mammals that lay eggs instead of giving birth to live young...

, also some shrew
Shrew
A shrew or shrew mouse is a small molelike mammal classified in the order Soricomorpha. True shrews are also not to be confused with West Indies shrews, treeshrews, otter shrews, or elephant shrews, which belong to different families or orders.Although its external appearance is generally that of...

 species), venomous spiny fish (e.g. stonefish
Stonefish
Synanceia verrucosa is a fish species, sometimes lethal to humans, which is known as the reef stonefish or simply stonefish. They are carnivorous ray-finned fish with venomous spines that lives on reef bottoms, camouflaged as a rock...

, butterfly cod, bullrout
Bullrout
The Bullrout, Notesthes robusta, also commonly called "Freshwater Stonefish" or "Kroki", is a pale yellowish to dark-brown coloured fish that lives in tidal estuaries and slow-flowing streams in eastern Australia, from Southern New South Wales, up to northern Queensland, Australia. It has on a...

, catfish
Catfish
Catfishes are a diverse group of ray-finned fish. Named for their prominent barbels, which resemble a cat's whiskers, catfish range in size and behavior from the heaviest and longest, the Mekong giant catfish from Southeast Asia and the second longest, the wels catfish of Eurasia, to detritivores...

, numerous other species), stingray
Stingray
The stingrays are a group of rays, which are cartilaginous fishes related to sharks. They are classified in the suborder Myliobatoidei of the order Myliobatiformes, and consist of eight families: Hexatrygonidae , Plesiobatidae , Urolophidae , Urotrygonidae , Dasyatidae , Potamotrygonidae The...

s. Phylum Arthropoda - spider
Spider
Spiders are air-breathing arthropods that have eight legs, and chelicerae with fangs that inject venom. They are the largest order of arachnids and rank seventh in total species diversity among all other groups of organisms...

s, scorpion
Scorpion
Scorpions are predatory arthropod animals of the order Scorpiones within the class Arachnida. They have eight legs and are easily recognized by the pair of grasping claws and the narrow, segmented tail, often carried in a characteristic forward curve over the back, ending with a venomous stinger...

s, tick
Tick
Ticks are small arachnids in the order Ixodida, along with mites, constitute the subclass Acarina. Ticks are ectoparasites , living by hematophagy on the blood of mammals, birds, and sometimes reptiles and amphibians...

s (only a few species are venomous, causing paralysis
Paralysis
Paralysis is loss of muscle function for one or more muscles. Paralysis can be accompanied by a loss of feeling in the affected area if there is sensory damage as well as motor. A study conducted by the Christopher & Dana Reeve Foundation, suggests that about 1 in 50 people have been diagnosed...

), centipede
Centipede
Centipedes are arthropods belonging to the class Chilopoda of the subphylum Myriapoda. They are elongated metameric animals with one pair of legs per body segment. Despite the name, centipedes can have a varying number of legs from under 20 to over 300. Centipedes have an odd number of pairs of...

s, some insect
Insect
Insects are a class of living creatures within the arthropods that have a chitinous exoskeleton, a three-part body , three pairs of jointed legs, compound eyes, and two antennae...

s (notably the hymenoptera
Hymenoptera
Hymenoptera is one of the largest orders of insects, comprising the sawflies, wasps, bees and ants. There are over 130,000 recognized species, with many more remaining to be described. The name refers to the heavy wings of the insects, and is derived from the Ancient Greek ὑμήν : membrane and...

ns including bee
Bee
Bees are flying insects closely related to wasps and ants, and are known for their role in pollination and for producing honey and beeswax. Bees are a monophyletic lineage within the superfamily Apoidea, presently classified by the unranked taxon name Anthophila...

s, wasp
Wasp
The term wasp is typically defined as any insect of the order Hymenoptera and suborder Apocrita that is neither a bee nor an ant. Almost every pest insect species has at least one wasp species that preys upon it or parasitizes it, making wasps critically important in natural control of their...

s and ant
Ant
Ants are social insects of the family Formicidae and, along with the related wasps and bees, belong to the order Hymenoptera. Ants evolved from wasp-like ancestors in the mid-Cretaceous period between 110 and 130 million years ago and diversified after the rise of flowering plants. More than...

s). Phylum Mollusca
Mollusca
The Mollusca , common name molluscs or mollusksSpelled mollusks in the USA, see reasons given in Rosenberg's ; for the spelling mollusc see the reasons given by , is a large phylum of invertebrate animals. There are around 85,000 recognized extant species of molluscs. Mollusca is the largest...

 - cone snail
Cone snail
Conidae is a taxonomic family of minute to quite large sea snails, marine gastropod molluscs in the superfamily Conoidea.The snails within this family are sophisticated predatory animals...

s and related predatory marine snails, some octopus
Octopus
The octopus is a cephalopod mollusc of the order Octopoda. Octopuses have two eyes and four pairs of arms, and like other cephalopods they are bilaterally symmetric. An octopus has a hard beak, with its mouth at the center point of the arms...

es (notably the blue-ringed octopus
Blue-ringed octopus
The blue-ringed octopuses are three octopus species that live in tide pools in the Pacific Ocean, from Japan to Australia . They are currently recognized as one of the world's most venomous marine animals...

). Phylum Cnidaria
Cnidaria
Cnidaria is a phylum containing over 9,000 species of animals found exclusively in aquatic and mostly marine environments. Their distinguishing feature is cnidocytes, specialized cells that they use mainly for capturing prey. Their bodies consist of mesoglea, a non-living jelly-like substance,...

 (Coelenterata
Coelenterata
Coelenterata is an obsolete term encompassing two animal phyla, the Ctenophora and the Cnidaria . The name comes from the Greek "koilos" , referring to the hollow body cavity common to these two phyla...

) - true jellyfish
Jellyfish
Jellyfish are free-swimming members of the phylum Cnidaria. Medusa is another word for jellyfish, and refers to any free-swimming jellyfish stages in the phylum Cnidaria...

, box jellyfish
Box jellyfish
Box jellyfish are cnidarian invertebrates distinguished by their cube-shaped medusae. Box jellyfish are known for the extremely potent venom produced by some species: Chironex fleckeri, Carukia barnesi and Malo kingi are among the most venomous creatures in the world...

 (contains some of the most lethal of all venomous animals), hydrozoa
Hydrozoa
Hydrozoa are a taxonomic class of very small, predatory animals which can be solitary or colonial and which mostly live in saltwater. A few genera within this class live in freshwater...

ns (includes colony "jellyfish" such as Physalia
Physalia
Physalia is a genus of the order Siphonophora, colonies of four specialized polyps and medusoids that drift on the surface of the Indian and Pacific oceans. A gas-filled bladder resembling a blue bottle maintains their buoyancy, and a single long tentacle of venomous cnidocytes provide the animal...

 or Portuguese Man O' War
Portuguese Man o' War
The Portuguese Man o' War , also known as the Portuguese man-of-war, man-of-war, or bluebottle, is a jelly-like marine invertebrate of the family Physaliidae...

), anthozoa
Anthozoa
Anthozoa is a class within the phylum Cnidaria that contains the sea anemones and corals. Unlike other cnidarians, anthozoans do not have a medusa stage in their development. Instead, they release sperm and eggs that form a planula, which attaches to some substrate on which the cnidarian grows...

ns (including coral
Coral
Corals are marine animals in class Anthozoa of phylum Cnidaria typically living in compact colonies of many identical individual "polyps". The group includes the important reef builders that inhabit tropical oceans and secrete calcium carbonate to form a hard skeleton.A coral "head" is a colony of...

). Phylum Echinodermata - sea urchin
Sea urchin
Sea urchins or urchins are small, spiny, globular animals which, with their close kin, such as sand dollars, constitute the class Echinoidea of the echinoderm phylum. They inhabit all oceans. Their shell, or "test", is round and spiny, typically from across. Common colors include black and dull...

s. This listing is not exhaustive.

Poisonous animals, mushrooms and plants again cover a diversity of taxonomic groups. In many cases, poisonous animals derive their poison from the environment. This applies to classic marine poisons such as fugu
Fugu
is the Japanese word for pufferfish and the dish prepared from it, normally species of genus Takifugu, Lagocephalus, or Sphoeroides, or porcupinefish of the genus Diodon. Fugu can be lethally poisonous due to its tetrodotoxin; therefore, it must be carefully prepared to remove toxic parts and to...

 (tetrodotoxin), ciguatera
Ciguatera
Ciguatera is a foodborne illness caused by eating certain reef fishes whose flesh is contaminated with toxins originally produced by dinoflagellates such as Gambierdiscus toxicus which lives in tropical and subtropical waters. These dinoflagellates adhere to coral, algae and seaweed, where they are...

, and the several distinct types of shellfish
Shellfish
Shellfish is a culinary and fisheries term for exoskeleton-bearing aquatic invertebrates used as food, including various species of molluscs, crustaceans, and echinoderms. Although most kinds of shellfish are harvested from saltwater environments, some kinds are found only in freshwater...

 poisons. In many cases the prime toxin producer is a dinoflagellate
Dinoflagellate
The dinoflagellates are a large group of flagellate protists. Most are marine plankton, but they are common in fresh water habitats as well. Their populations are distributed depending on temperature, salinity, or depth...

. Conversely, mushroom and plant toxins are produced by the organism itself. Plant toxins have long been recognised as poisons, but also as therapeutic agents, if used in the correct dose. A classic example is digitalis
Digitalis
Digitalis is a genus of about 20 species of herbaceous perennials, shrubs, and biennials that are commonly called foxgloves. This genus was traditionally placed in the figwort family Scrophulariaceae, but recent reviews of phylogenetic research have placed it in the much enlarged family...

, long used as treatment for certain heart conditions
Heart disease
Heart disease, cardiac disease or cardiopathy is an umbrella term for a variety of diseases affecting the heart. , it is the leading cause of death in the United States, England, Canada and Wales, accounting for 25.4% of the total deaths in the United States.-Types:-Coronary heart disease:Coronary...

. Nevertheless, some plant toxins have become "popular" as self-harm
Self-harm
Self-harm or deliberate self-harm includes self-injury and self-poisoning and is defined as the intentional, direct injuring of body tissue most often done without suicidal intentions. These terms are used in the more recent literature in an attempt to reach a more neutral terminology...

 agents, used in suicide
Suicide
Suicide is the act of intentionally causing one's own death. Suicide is often committed out of despair or attributed to some underlying mental disorder, such as depression, bipolar disorder, schizophrenia, alcoholism, or drug abuse...

s. Mushroom toxins include some lethal toxins that can cause painful, drawn out death.

Clinical toxinology

Within toxinology there is a clinical subgroup, clinical toxinologists, who focus on the medical effects in humans of exposure to the toxins in animal venoms or plant poisons. This includes such problems as venomous snakebite, currently considered to afflict >2.5 million people each year, with >100,000 deaths. Information on these medical consequences of toxins can be found in diverse sources, such as the Clinical Toxinology Resources Website and books such as Prof. Mebs book and the CRC book on toxinology. Clinical toxinology does not, yet, enjoy specialist status within medicine, unlike fields such as surgery
Surgery
Surgery is an ancient medical specialty that uses operative manual and instrumental techniques on a patient to investigate and/or treat a pathological condition such as disease or injury, or to help improve bodily function or appearance.An act of performing surgery may be called a surgical...

 and radiology
Radiology
Radiology is a medical specialty that employs the use of imaging to both diagnose and treat disease visualized within the human body. Radiologists use an array of imaging technologies to diagnose or treat diseases...

. However, a training course in clinical toxinology has existed since 1997 (held in Adelaide
Adelaide
Adelaide is the capital city of South Australia and the fifth-largest city in Australia. Adelaide has an estimated population of more than 1.2 million...

, Australia
Australia
Australia , officially the Commonwealth of Australia, is a country in the Southern Hemisphere comprising the mainland of the Australian continent, the island of Tasmania, and numerous smaller islands in the Indian and Pacific Oceans. It is the world's sixth-largest country by total area...

) and efforts are under way to expand this to a true, specialist-level international training program, through an initiative of the International Society on Toxinology. Given the huge impact of toxin-based disease globally, the value of having doctors expert in this area is self evident.

External links

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