Monosodium methyl arsenate

Monosodium methyl arsenate
IUPAC name Sodium hydrogen methylarsonate
Other names Monosodium methyl arsenate; sodium methylarsonate; monosodium methane arsonate; methyl arsonic acid monosodium salt; EPA Pesticide Chemical Code 013803
Identifiers
Abbreviations	MSMA
CAS number	2163-80-6 Y
PubChem	23664719
ChemSpider	13732108 Y
Jmol-3D images	Image 1
SMILES [Na+].[O-][As]([O-])(=O)OC
InChI InChI=1S/CH5AsO4.Na/c1-6-2(3,4)5;/h1H3,(H2,3,4,5);/q;+1/p-2 Y Key: RDXKFMGONHCKSA-UHFFFAOYSA-L Y InChI=1/CH5AsO4.Na/c1-6-2(3,4)5;/h1H3,(H2,3,4,5);/q;+1/p-2 Key: RDXKFMGONHCKSA-NUQVWONBAT
Properties
Molecular formula	CH4AsNaO3
Molar mass	161.95 g/mol
Y (verify) (what is: Y/N?) Except where noted otherwise, data are given for materials in their standard state (at 25 °C, 100 kPa)
Infobox references

Monosodium methyl arsenate (MSMA) is an arsenic-based herbicide and fungicide. It is an organic arsenate; but it is a less toxic organic form of arsenic, which has replaced the role of lead hydrogen arsenate in agriculture. It is one of the most common herbicides used on golf courses. It is typically used for control of grassy weeds such as crabgrass. Another common use is for burning the marked lines into grassy sports fields.

Some of its trade names include Ansar 170, Ansar 170L, Ansar 529, Ansar 529 HC, Ansar 6.6, Asazol, Bueno, Bueno 6, CCRIS 4676, Caswell No. 582, Daconate, Daconate 6, Dal-E-Rad, Dal-E-Rad 120, Drexar, Gepiron, HSDB 754, Herb-All, Herban M, Merge, Merge 823, Mesamate, Mesamate H.C., Mesamate-400, and Mesamate-600.

See also

• Cacodylic acid
• Disodium methyl arsenate

References

• The MAA Research Task Force (MAATF)
• Case Studies in Environmental Medicine - Arsenic Toxicity
• NLM Hazardous Substances Databank – Sodium methanarsenate