Trimethylarsine

Structural formula
General
Surname	Trimethylarsine
other names	Trimethylarsane; TMA (not clear, see TMA );
Molecular formula	C 3 H 9 As
Brief description	colorless liquid
External identifiers / databases
EC number	209-815-8
ECHA InfoCard	100.008.925
PubChem	68978
Wikidata	Q421500
properties
Molar mass	120.02 g mol −1
Physical state	liquid
density	1.133 g cm −3
Melting point	−87.3 ° C
boiling point	52 ° C
solubility	almost insoluble in water
safety instructions
H and P phrases	H: 331-301-410
	P: ?
Toxicological data	7870 mg kg −1 ( LD 50 , mouse , oral ) ; 90 mg kg −1 ( LD 50 , mouse , iv ) ; 6000 mg kg −1 ( LC 50 , Mammalia , inh. ) ; 20,500 ppm · 10 min ( LC 50 , mouse , inh. ) ;
	As far as possible and customary, SI units are used. Unless otherwise noted, the data given apply to standard conditions .

Trimethylarsine , also referred to as trimethylarsane according to IUPAC , is an organometallic compound with the constitutional formula (CH ₃ ) ₃ As. It is an arsenic-containing , easily evaporable liquid substance, the smell of which is reminiscent of garlic. It was discovered in 1854.

Occurrence and toxicology

Trimethylarsine is produced in bacteria and fungi by the reduction of arsenic (V) compounds with subsequent methylation. The metabolism of mammals, on the other hand, converts arsenic to dimethylarsine compounds such as dimethylarsinic acid (also known as cacodylic acid ), which can be excreted in the urine. The life-threatening dangers emanating from arsenic compounds are based on the reaction with sulfur-containing proteins , the associated inhibition of the citrate cycle and the interruption of the substrate chain phosphorylation within glycolysis .

history

Bartolomeo Gosio discovered that the fungus Scopulariopsis brevicaulis generates gases containing arsenic from rotting wallpaper with color pigments containing metal . Leopold Gmelin and many other chemists then campaigned for a ban on arsenic-containing paints. The chemist Frederick Challenger identified the gas as trimethylarsine in 1932.

Recent toxicological studies seem to contradict the assumption that trimethylarsine is responsible for the considerable health effects of the arsenic-containing wallpapers, although experts do not agree on this.

Individual evidence

↑ ^a ^b Trimethylarsine data sheet (PDF) from Strem, accessed on December 25, 2012.

↑ Trimethylarsine data sheet from Sigma-Aldrich , accessed on April 24, 2011 ( PDF ).

^ ^A ^b A. F. Holleman , E. Wiberg , N. Wiberg : Textbook of Inorganic Chemistry . 102nd edition. Walter de Gruyter, Berlin 2007, ISBN 978-3-11-017770-1 .

↑ Entry on arsenic compounds in the GESTIS substance database of the IFA , accessed on February 1, 2016 (JavaScript required)

↑ Not explicitly listed in Regulation (EC) No. 1272/2008 (CLP) , but with the specified labeling it falls under the group entry arsenic compounds, with the exception of those named in this appendix in the Classification and Labeling Inventory of the European Chemicals Agency (ECHA) on February 1, 2016. Manufacturers or distributors can expand the harmonized classification and labeling .

↑ ^a ^b Entry on trimethylarsine in the ChemIDplus database of the United States National Library of Medicine (NLM) .

^ ^A ^b Sax, NI: Dangerous Properties of Industrial Materials , Van Nost. Reinhold, April 1984, ISBN 978-0-442-28304-9

↑ R. Braun (Ed.): Special toxicology for chemists: A selection of toxic substances , BG Teubner Verlag, 1999, pp. 72–73, ISBN 3-519-03538-3

↑ Ronald Bentley & Thomas G. Chasteen (2002): Microbial Methylation of Metalloids: Arsenic, Antimony, and Bismuth. In: Microbiol. Mol. Biol. Rev. Vol. 66, pp. 250-271. PMID 12040126 PDF

↑ Jutta Kresimon: Analysis of human body fluids and excretion products for organometallic and metalloid organic compounds using HG / LT-GC / ICP-MS. Dissertation. Essen, 2002

↑ H. Yamauchi et al. (1990): Toxicity and metabolism of trimethylarsine in mice and hamsters. In: Fundam. Appl. Toxicol. Vol. 14, pp. 399-407. PMID 2318361

^ William R. Cullen & Ronald Bentley (2005): The toxicity of trimethylarsine: an urban myth. In: J Environ Monit . Vol. 7, pp. 11-15. PMID 15693178 doi : 10.1039 / b413752n

[Strem-1] Trimethylarsine data sheet (PDF) from Strem, accessed on December 25, 2012.