Editing Tabun (nerve agent) (section)

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| Verifiedfields = changed
| Watchedfields = changed
| verifiedrevid = 476997516
| Name = Tabun
| ImageFile1 = GA-3D-balls-by-AHRLS-2011.png
| ImageClass1 = bg-transparent
| ImageSize1 = 
| ImageFile2 = Tabun.svg
| ImageClass2 = skin-invert-image
| ImageSize2 = 
| IUPACName = (''RS'')-Ethyl ''N'',''N''-Dimethylphosphoramidocyanidate
| OtherNames = GA; Ethyl dimethylphosphoramidocyanidate; Dimethylaminoethoxy-cyanophosphine oxide; Dimethylamidoethoxyphosphoryl cyanide; Ethyl dimethylaminocyanophosphonate; Ethyl ester of dimethylphosphoroamidocyanidic acid; Ethyl phosphorodimethylamidocyanidate; Cyanodimethylaminoethoxyphosphine oxide; Dimethylaminoethodycyanophosphine oxide; EA-1205; TL-1578
|Section1={{Chembox Identifiers
| Abbreviations =
| ChemSpiderID_Ref = {{chemspidercite|correct|chemspider}}
| ChemSpiderID = 6254
| ChEMBL_Ref = {{ebicite|changed|EBI}}
| ChEMBL = 1097650
| InChI = 1/C5H11N2O2P/c1-4-9-10(8,5-6)7(2)3/h4H2,1-3H3
| InChIKey = PJVJTCIRVMBVIA-UHFFFAOYAG
| StdInChI_Ref = {{stdinchicite|correct|chemspider}}
| StdInChI = 1S/C5H11N2O2P/c1-4-9-10(8,5-6)7(2)3/h4H2,1-3H3
| StdInChIKey_Ref = {{stdinchicite|correct|chemspider}}
| StdInChIKey = PJVJTCIRVMBVIA-UHFFFAOYSA-N
| CASNo_Ref = {{cascite|correct|CAS}}
| CASNo = 77-81-6
| UNII_Ref = {{fdacite|correct|FDA}}
| UNII = S45M750QSH
| EINECS =
| PubChem = 6500
| SMILES = N#CP(=O)(OCC)N(C)C
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| ChEBI_Ref = {{ebicite|correct|EBI}}
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| KEGG_Ref = {{keggcite|correct|kegg}}
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}}
|Section2={{Chembox Properties
| C=5 | H=11 | N=2 | O=2 | P=1
| Appearance = Colorless to brown liquid
| Density = 1.0887 g/cm<sup>3</sup> at 25 °C<br />1.102 g/cm<sup>3</sup> at 20 °C
| MeltingPtC = -50
| BoilingPtC = 247.5
| Solubility = 9.8 g/100 g at 25 °C <br /> 7.2 g/100 g at 20 °C
| SolubleOther =
| Solvent =
| LogP =
| VaporPressure = 0.07 mmHg (9 Pa)
| HenryConstant =
| AtmosphericOHRateConstant =
| pKa =
| pKb = }}
|Section5={{Chembox Pharmacology
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| Pregnancy_US = }}
|Section7={{Chembox Hazards
| ExternalSDS =
| MainHazards = Highly toxic.  Fires involving this chemical may result in the formation of [[hydrogen cyanide]]
| NFPA-H = 4
| NFPA-F = 2
| NFPA-R = 1
| NFPA-S =
| HPhrases = 
| PPhrases = 
| GHS_ref  = 
| FlashPtC = 78
| AutoignitionPtC = 
| ExploLimits =
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| PEL = }}
|Section8={{Chembox Related
| OtherAnions =
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}}

'''Tabun''' (military designation '''GA''') is an extremely toxic compound of the [[organophosphate]] family.<ref>{{Cite journal |date=2021-10-02 |title=CBRNE - Nerve Agents, G-series - Tabun, Sarin, Soman: Practice Essentials, Pathophysiology, Epidemiology |url=https://emedicine.medscape.com/article/831648-overview |journal=[[Medscape]]}}</ref><ref name=":0">{{Cite journal |date=2021-10-02 |title=CBRNE - Nerve Agents, G-series - Tabun, Sarin, Soman: Practice Essentials, Pathophysiology, Epidemiology |url=https://emedicine.medscape.com/article/831648-overview |journal=[[CBRNE]] |at=Pathophysiology |via=Medscape}}</ref> It is not present in nature. At room temperature, the pure compound is a clear and viscous liquid. However, impurities imparted during its manufacture are almost always present, turning it into a yellow or brown liquid. Exposed to environs, it slowly volatizes into the atmosphere,<ref>{{Cite web |title=NRT CBRN Tabun 2022 07 26.pdf |url=https://nrt.org/sites/2/files/NRT%20CBRN%20CHEM%20UPDATE%20Tabun%20GA%20QRG%20FINAL%202022%2007%2026.pdf |website=NRT.org}}</ref> with the vapor having a slight fruity or almond-like odor.<ref name=":1">{{Cite web |date=2024-04-26 |title=Tabun (GA): Nerve Agent {{!}} NIOSH {{!}} CDC |url=https://www.cdc.gov/niosh/ershdb/emergencyresponsecard_29750004.html |access-date=2024-07-26 |website=www.cdc.gov |language=en-us}}</ref> As the compound has a much higher [[molecular mass]] (162 g/mol) compared to air, Tabun gas tends to accumulate in low-lying areas.<ref name=":1" />

It is a potent inhibitor of [[acetylcholinesterase]], a key [[enzyme]] within the human body as well as in other animals.<ref name="PubChem 6500 Tabun">{{PubChem|6500|Tabun}}</ref> Acetylcholinesterase is responsible for breaking down [[acetylcholine]], a [[neurotransmitter]] released into the [[Chemical synapse|synaptic cleft]] by motor neurons. The presence of acetylcholine within the cleft signals the post-synaptic (downstream) motor neuron to contract the neuron's associated [[Muscle cell|muscle fibers]], and vice versa. By irreversibly [[Phosphorylation|phosphorylating]] the enzyme,<ref name=":0" /> Tabun accomplishes a constant and involuntary contraction of the affected muscles, as the acetylcholine is not recycled and continues to build up within the cleft. Death of the organism ensues when respiratory muscles, such as the [[Thoracic diaphragm|diaphragm]] and [[Internal intercostal muscles|intercostals]], become exhausted and paralyzed from constant contraction, leading to loss of respiratory functions.<ref name=":0" />

The production and storage of Tabun has been strictly regulated under the [[Chemical Weapons Convention]] and its implementing agency [[Organisation for the Prohibition of Chemical Weapons|OPCW]] since 1997.<ref>{{cite book |doi=10.1016/B978-0-12-801238-3.97320-3 |chapter=Tabun |title=Reference Module in Biomedical Sciences |date=2017 |last1=Poindexter |first1=Kirstin |last2=Pope |first2=Carey |isbn=978-0-12-801238-3 }}</ref><ref>{{cite book |doi=10.1016/B978-0-12-824315-2.00545-5 |chapter=Tabun |title=Encyclopedia of Toxicology |date=2024 |last1=Hajimohammadi |first1=Samaneh |last2=Balali-Mood |first2=Mahdi |last3=Etemad |first3=Leila |last4=Moshiri |first4=Mohammad |pages=901–912 |isbn=978-0-323-85434-4 }}</ref> As a Schedule 1 Toxic Chemical,<ref>{{Cite web |title=Schedule 1 |url=https://www.opcw.org/chemical-weapons-convention/annexes/annex-chemicals/schedule-1 |access-date=2024-07-26 |website=OPCW |language=en}}</ref> the synthesis of more than 100 grams of the substance per year must be declared to the organization, and no signing nation can possess more than 1 ton of the chemical.<ref>{{Cite web |title=Chemical Weapons Convention - CWC_en.pdf |url=https://www.opcw.org/chemical-weapons-convention/download-convention |access-date=2024-07-26 |website=OPCW |page=4 |language=en}}</ref> Modern usage of Tabun is limited to research purposes in minute amounts.<ref>{{Cite web |title=Chemical Weapons Convention - CWC_en.pdf |url=https://www.opcw.org/chemical-weapons-convention/download-convention |access-date=2024-07-26 |website=OPCW |page=124 |language=en}}</ref>