disodium methyl arsonate

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| verifiedrevid = 432422543

| ImageFile=Disodium methyl arsenate.png

| ImageSize=150px

| ImageFile1 = Disodium-methyl-arsenate-3D-balls.png

| ImageSize1 = 200

| ImageAlt1 = Two sodium cations and one methyl arsenate anion

| IUPACName=Disodium methyl-dioxido-oxoarsorane

| OtherNames=Disodium methanearsonate; disodium methylarsonate

|Section1={{Chembox Identifiers

| Abbreviations = DSMA

| CASNo_Ref = {{cascite|correct|??}}

| CASNo=144-21-8

| UNII_Ref = {{fdacite|correct|FDA}}

| UNII = 7NK4BV40VN

| PubChem=8947

| SMILES=C[As](=O)([O-])[O-].[Na+].[Na+]

| ChemSpiderID_Ref = {{chemspidercite|changed|chemspider}}

| ChemSpiderID = 8603

| InChI = 1/CH5AsO3.2Na/c1-2(3,4)5;;/h1H3,(H2,3,4,5);;/q;2*+1/p-2

| InChIKey = SDIXRDNYIMOKSG-NUQVWONBAA

| StdInChI_Ref = {{stdinchicite|changed|chemspider}}

| StdInChI = 1S/CH5AsO3.2Na/c1-2(3,4)5;;/h1H3,(H2,3,4,5);;/q;2*+1/p-2

| StdInChIKey_Ref = {{stdinchicite|changed|chemspider}}

| StdInChIKey = SDIXRDNYIMOKSG-UHFFFAOYSA-L

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|Section2={{Chembox Properties

| Formula=CH₃AsNa₂O₃

| MolarMass=183.93 g/mol

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|Section3={{Chembox Hazards

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Disodium methyl arsenate (DSMA) is the organoarsenic compound with the formula CH3AsO3Na2. It is a colorless, water-soluble solid derived from methanearsonic acid. It is used as a herbicide.{{Ullmann | author = Grund, S. C. | author2 = Hanusch, K. | author3 = Wolf, H. U. | title = Arsenic and Arsenic Compounds | doi = 10.1002/14356007.a03_113.pub2 }} Tradenames include Metharsinat, Arrhenal, Disomear, Metharsan, Stenosine, Tonarsan, Tonarsin, Arsinyl, Arsynal, and Diarsen.

The EPA states that all forms of arsenic are a serious risk to human health and the United States' Agency for Toxic Substances and Disease Registry ranked arsenic as number 1 in its 2001 Priority List of Hazardous Substances at Superfund sites.{{cite web |url=https://cfpub.epa.gov/ncer_abstracts/index.cfm/fuseaction/display.highlight/abstract/6015 |title=Biogeochemistry of Arsenic in Contaminated Soils of Superfund Sites |last1=Dibyendu |first1=Sarkar |last2=Datta |first2=Rupali |date=2007 |website=EPA |publisher=United States Environmental Protection Agency |access-date=25 February 2018 }} Arsenic is classified as a Group-A carcinogen. The EPA states{{cite web |url=https://cfpub.epa.gov/ncer_abstracts/index.cfm/fuseaction/display.highlight/abstract/6015/report/F |title=Final Report: Biogeochemistry of Arsenic in Contaminated Soils of Superfund Sites |last=Carelton |first=James |date=2007 |website=EPA |publisher=United States Environmental Protection Agency |access-date=25 February 2018 }} that:

{{quote|Arsenate (AsV) is the oxidized form and occurs in well-aerated soils, whereas in chemically-reduced soil environments, arsenite (AsIII) is the prevalent As form. Although arsenite is more toxic than arsenate, arsenate can also have deleterious effects on humans, plants, and microorganisms. Arsenic-contaminated soils pose serious risk to human health.}}

The EPA also states that, while contaminated soil poses a serious risk to health, arsenic frequently mobilizes from soils and other sources, ending up in water where it is even more of a toxicity issue.