Methyl bromide

Description

A colorless gas used as an insect Fumigant and as a Solvent. Methyl bromide has a weak chloroform-like odor at high concentrations but provides no warning odor at normal usage levels. Methyl bromide has been used extensively for control of wood boring insects, but it is no longer recommended for use in museums. It is currently used for fumigating crops and soil and is registered for use as a space fumigant. Methyl bromide reacts with basic amines. It also reacts with sulfur containing materials to form foul-smelling mercaptans, thio-ethers, and disulfides. This unpleasant odor can remain for several weeks. The following materials should not be fumigated with methyl bromide: vulcanized rubber sponge, Foam rubber, vulcanized Natural rubber, Fur, Hair, feathers, Leather, Vellum, Parchment, Wool, Silk, Viscose rayon, Paper, silver polishing papers, Color film, photographs, and photographic chemicals. Some impurities in methyl bromide may corrode Zinc, Tin, Lead, and Iron. Methyl bromide can also dissolve drying oils.

Synonyms and Related Terms

bromomethane; monobromomethane; Embafume; Brom-O-Gas; Methogas; Terr-O-Gas; maltox

Other Properties

Soluble in ethanol, chloroform, ether, carbon disulfide, carbon tetrachloride, benzene. Methyl bromide is used to extract oils from seeds, nuts and flowers.

Composition	CH3Br
CAS	74-83-9
Melting Point	-93.66
Molecular Weight	mol. wt. = 94.9
Boiling Point	3.56

Hazards and Safety

Toxic by inhalation, ingestion and skin absorption. TLV=65 mg/m3

Skin contact causes irritation and burns. Potential carcinogen and teratogen.

Combustible. Burning produces toxic fumes including hydrogen bromide, bromine and carbon oxybromide.

LINK: International Chemical Safety Card

Additional Information

° Dow Chemical. "Commodities unsuited for methyl bromide fumigation" Dow Fumifacts, 4:2 (1957).

° J.Dawson, "Solving Museum Insect Problems: Chemical Control" CCI Technical Bulletin No. 15.

° L. Goldberg, A History Of Pest Control Measures In The Anthropology Collections, National Museum Of Natural History, Smithsonian Institution, JAIC (35):23-43, 1996

Sources Checked for Data in Record

• Richard S. Lewis, Hawley's Condensed Chemical Dictionary, Van Nostrand Reinhold, New York, 10th ed., 1993

• The Merck Index, Martha Windholz (ed.), Merck Research Labs, Rahway NJ, 10th edition, 1983 Comment: entry 6108

• Lynda A. Zycherman, J.Richard Schrock, A Guide to Museum Pest Control, FAIC and Association of Systematics Collections, Washington DC, 1988

• Matt Roberts, Don Etherington, Bookbinding and the Conservation of Books: a Dictionary of Descriptive Terminology, U.S. Government Printing Office, Washington DC, 1982

• J. Dawson, CCI Technical Bulletin, 'Solving Museum Insect Problems: Chemical Control' , Canadian Conservation Institute, Ottawa, No. 15

• Hermann Kuhn, Conservation and Restoration of Works of Art and Antiquities, Butterworths, London, 1986

• Stephen R. Edwards, Bruce M. Bell, Mary Elizabeth King, Pest Control in Museums: a Status Report 1980, Association of Sytematics Collections, Washington DC, 1980

• G.Caneva, M.P.Nugari, O.Salvadori, Biology in the Conservation of Works of Art, ICCROM, Rome, 1991