An organophosphate (sometimes abbreviated OP) is the general name for esters of phosphoric acid and is one of the organophosphorus compounds. They can be found as part of insecticides, herbicides, and nerve gases, amongst others. Some less-toxic organophosphates can be used as solvents, plasticizers, and EP additives. Early pioneers in the field include Lassaigne (early 1800s) and Philip de Clermount (1854). General formula of a carboxylate ester. ... Phosphoric acid, also known as orthophosphoric acid or phosphoric(V) acid, is an inorganic mineral acid having the chemical formula H3PO4. ... Organophosphorus compounds are chemical compounds containing carbon phosphorus bonds. ... A insecticide is a pesticide used against insects in all development forms. ... This article or section does not cite its references or sources. ... Also known as Nerve agents, it is the term used for a type of chemical warfare substance that interferes with the transmission of nerve impulses. ... A solvent is a fluid phase (liquid, gas, or plasma) that dissolves a solid, liquid, or gaseous solute, resulting in a solution. ... Plasticizers are additives that soften the materials (usually a plastic or a concrete mix) they are added to. ... EP (extreme pressure) additives are a range of organophosphates including sulfur-phosphorous and sulfur-phosphorous-boron which are used in motor oils to provide better engine gear protection as an alternative to graphite additives. ... Events and Trends Beginning of the Napoleonic Wars (1803 - 1815). ... 1854 was a common year starting on Sunday (see link for calendar). ...

The term organophosphate should strictly be reserved for an ester of phosphoric acid or one of its higher compounds (such as pyrophosphoric acid. But the term is used often to describe any organic phosphorus-containing compound, especially when dealing with neurotoxins. Many of the so called organophosphates contain C-P bonds which make them something else, for instance sarin is O-Isopropyl Methylphosphonofluoridate whose parent phosphorus acid is HP(O)(OH)₂ which is phosphorous acid not phosphoric acid. Also many compounds which are derivatives of phosphinic acid are used as organic phosphorus containing neurotoxin. General formula of a carboxylate ester. ... Phosphoric acid, also known as orthophosphoric acid or phosphoric(V) acid, is an inorganic mineral acid having the chemical formula H3PO4. ... Pyrophosphoric acid, also known under the name diphosphoric acid, is a syrupy liquid or a needle-like crystaline solid. ... Sarin or GB (O-Isopropyl methylphosphonofluoridate) is an extremely toxic substance. ... The compound phosphorous acid, with formula H3PO3, is an oxoacid of phosphorus. ... Phosphoric acid, also known as orthophosphoric acid or phosphoric(V) acid, is an inorganic mineral acid having the chemical formula H3PO4. ... Hypophosphorous acid is a phosphorus oxoacid and a powerful reducing agent. ...

Overview of 'Organophosphate' neurotoxins

Basics

To act as an 'Organophosphate' neurotoxins the following structural requirements exist.

• A terminal oxygen bonded by a double bond to the phosphorus
• Two lipophilic groups bonded to the phosphorus
• A leaving group bonded to the phosphorus

General Name, Symbol, Number oxygen, O, 8 Chemical series Nonmetals, chalcogens Group, Period, Block 16, 2, p Appearance colorless (gas) very pale blue (liquid) Atomic mass 15. ... This article is about the chemical element. ... A leaving group is an atom or molecule that detaches from an organic molecule, which, after detachment, is called the residual or main part. ...

Terminal oxygen vs. terminal sulfur

Note that these compounds bearing terminal sulfur atoms on the phosphorus atom are much less toxic than the compounds (such as sarin, VX and tetraethyl pyrophosphate) which have an oxygen in place of this terminal sulfur. This is because the P=S compound is not active as an acetylcholinesterase inhibitor in either mammals or insects, in mammals the animals metabolism tends to remove lipophilic side groups from the phosphorus atom while an insect tends to oxidise the compound so removing the terminal sulfur and replacing it with a terminal oxygen which causes the compound to be more able to act as an acetylcholinesterase inhibitor. General Name, Symbol, Number sulfur, S, 16 Chemical series nonmetals Group, Period, Block 16, 3, p Appearance lemon yellow Atomic mass 32. ... General Name, Symbol, Number sulfur, S, 16 Chemical series nonmetals Group, Period, Block 16, 3, p Appearance lemon yellow Atomic mass 32. ... This article is about the chemical element. ... Sarin or GB (O-Isopropyl methylphosphonofluoridate) is an extremely toxic substance. ... The VX nerve agent is the most well-known of the V-series of nerve agents. ... General Name, Symbol, Number oxygen, O, 8 Chemical series Nonmetals, chalcogens Group, Period, Block 16, 2, p Appearance colorless (gas) very pale blue (liquid) Atomic mass 15. ... In biochemistry, cholinesterase is a term which refers to one of the two enzymes (EC 3. ... An enzyme inhibitor is a molecule that binds to an enzyme and decreases its rate of reaction. ... Orders Subclass Monotremata Monotremata Subclass Marsupialia Didelphimorphia Paucituberculata Microbiotheria Dasyuromorphia Peramelemorphia Notoryctemorphia Diprotodontia Subclass Placentalia Xenarthra Dermoptera Desmostylia Scandentia Primates Rodentia Lagomorpha Insectivora Chiroptera Pholidota Carnivora Perissodactyla Artiodactyla Cetacea Afrosoricida Macroscelidea Tubulidentata Hyracoidea Proboscidea Sirenia The mammals are the class of vertebrate animals primarily characterized by the presence of mammary... Santorio Santorio (1561-1636) in his steelyard balance, from Ars de statica medecina, first published 1614 Metabolism (from μεταβολισμος (metabolismos)) is the biochemical modification of chemical compounds in living organisms anggjgjhnd cell (b). ... This article or section does not cite its references or sources. ...

Fine tuning

Within these requirements a large number of different lipophilic and leaving groups have been used. The variation of these groups is one means of fine tuning the toxicity of the compound.

Example

A good example of this chemistry are the P-thiocyanate compounds which use an aryl (or alkyl) group and an alkylamino group as the lipophilic groups. The thiocyanate is the leaving group. Thiocyanate (also known as sulphocyanate or thiocyanide) is both an anion SCN- and, in organic chemistry, a functional group: An example of the anion is found in potassium thiocyanate, KSCN. Thiocyanate is analogous to the cyanate ion, OCN-, wherein oxygen is replaced by sulfur. ... In the context of organic molecules, aryl refers to any member of the set of functional groups or substituents that are derived from a simple aromatic ring. ... An alkyl is a univalent radical containing only carbon and hydrogen atoms arranged in a chain. ...

One of the products of the reaction of Fc₂P₂S₄ with dimethyl cyanamide

It was claimed in a German patent that the reaction of 1,3,2,4-dithiadiphosphetane 2,4-disulfides with dialkyl cyanamides formed plant protection agents which contained six membered (P-N=C-N=C-S-) rings. It has been proven in recent times by the reaction of diferrocenyl 1,3,2,4-dithiadiphosphetane 2,4-disulfide (and Lawesson's reagent) with dimethyl cyanamide that in fact a mixture of several different phosphorus containing compounds is formed. Depending on the concentration of the dimethyl cyanamide in the reaction mixture either a different six membered ring compound (P-N=C-S-C=N-) or a nonheterocylic compound (FcP(S)(NR2)(NCS)) is formed as the major product, the other compound is formed as a minor product. Image File history File links FcPthiocyanate2. ... Image File history File links FcPthiocyanate2. ... Six can refer to: 6 (number), a number Six (cricket), when a batsman in cricket hits the ball to or over the boundary without the ball touching the ground inside the boundary first Six, a character on the television series Blossom (television) Six (television) or Channel 6, a proposed satellite... Cyanamide (CN2H2) is an amide of cyanogen, a white, crystalline compound. ... This article is about the chemical element. ...

In addition small traces of other compounds are also formed in the reaction. It is unlikely that the ring compound (P-N=C-S-C=N-) {or its isomer} would act as a plant protection agent, but (FcP(S)(NR2)(NCS)) compounds can act as nerve poisons in insects. Nerves (yellow) Nerves redirects here. ... Orders Subclass Apterygota Symphypleona - globular springtails Subclass Archaeognatha (jumping bristletails) Subclass Dicondylia Monura - extinct Thysanura (common bristletails) Subclass Pterygota Diaphanopteroidea - extinct Palaeodictyoptera - extinct Megasecoptera - extinct Archodonata - extinct Ephemeroptera (mayflies) Odonata (dragonflies and damselflies) Infraclass Neoptera Blattodea (cockroaches) Mantodea (mantids) Isoptera (termites) Zoraptera Grylloblattodea Dermaptera (earwigs) Plecoptera (stoneflies) Orthoptera (grasshoppers, crickets...

Organophosphate poisoning (see nerve gas)

Many organophosphates are potent neurotoxins, functioning by inhibiting the action of acetylcholinesterase (AChE) in nerve cells. Also known as Nerve agents, it is the term used for a type of chemical warfare substance that interferes with the transmission of nerve impulses. ... The International Statistical Classification of Diseases and Related Health Problems (commonly known by the abbreviation ICD) is a detailed description of known diseases and injuries. ... The following codes are used with International Statistical Classification of Diseases and Related Health Problems. ... // S00-T98 - Injury, poisoning and certain other consequences of external causes (S00-S09) Injuries to the head (S00) Superficial injury of head (S01) Open wound of head (S02) Fracture of skull and facial bones (S03) Dislocation, sprain and strain of joints and ligaments of head (S04) Injury of cranial nerves... The International Statistical Classification of Diseases and Related Health Problems (commonly known by the abbreviation ICD) is a detailed description of known diseases and injuries. ... The following is a list of codes for International Statistical Classification of Diseases and Related Health Problems. ... It has been suggested that Neurotoxicity be merged into this article or section. ... In biochemistry, cholinesterase is a term which refers to one of the two enzymes (EC 3. ... Nerves (yellow) Nerves redirects here. ... Cells in culture, stained for keratin (red) and DNA (green). ...

The effects of organophosphate poisoning are recalled using the mnemonic "SLUD" or "SLUDGE", for salivation, lacrimation, urination, defecation, gastrointestinal upset, and emesis. SLUD (Salivation, Lacrimation, Urination, Defecation [and emesis]). A syndrome of pathological effects indicative of massive discharge of the parasympathetic nervous system. ... For the band, see Saliva (band). ... Tears trickling down the cheeks Lacrimation is the bodys process of producing tears, which are a liquid to clean and lubricate the eyes. ... Urination, also called micturition, is the process of disposing urine from the urinary bladder through the urethra to the outside of the body. ... Anatomy of the anus and rectum Defecation or feceation is the act or process by which organisms eliminate solid or semisolid waste material from the digestive tract. ... Vomiting (or emesis) is the forceful expulsion of the contents of ones stomach through the mouth. ...

Atropine can be used as an antidote. Atropine is a tropane alkaloid extracted from the deadly nightshade (Atropa belladonna) and other plants of the family Solanaceae. ... An antidote is a substance which can counteract a form of poisoning. ...

Purdey (1998) suggested that organophosphates, in particular Phosmet induced the transmissible spongiform encephalopathy epidemic of BSE. An European Union food safety Scientific Steering Committee examined the evidence and did not find a link[1]. Phosmet is a non-systemic, organophosphate insecticide used on plants and animals. ... Transmissible spongiform encephalopathies (TSEs) are fatal degenerative diseases of the brain transmitted by prions with no cure. ... Look up Bovine spongiform encephalopathy in Wiktionary, the free dictionary. ...

References

• Purdey M. High-dose exposure to systemic phosmet insecticide modifies the phosphatidylinositol anchor on the prion protein: the origins of new variant transmissible spongiform encephalopathies? Med Hypotheses 1998;50:91-111. PMID 9572563.

Phosmet is a non-systemic, organophosphate insecticide used on plants and animals. ... A prion (IPA: [1] ) — short for proteinaceous infectious particle — is a unique type of infectious agent, as it is made only of protein. ...

External links

• Organophosphate insecticides fact sheet
• Organophosphates - an article by Frances M Dyro, MD