Agent Name

Methyl bromide

Alternative Name

Bromomethane

CAS Number

74-83-9

Formula

C-H3-Br

Major Category

Pesticides

Synonyms

Bromomethane; Monobromomethane; [NIOSH]

Category

Fumigants

Description

Colorless gas with a chloroform-like odor at high concentrations. [Note: A liquid below 38 degrees F. Shipped as a liquefied compressed gas.] [NIOSH]

Sources/Uses

Used as a fumigant, and in the synthesis of organic chemicals; no longer used as a refrigerant or fire extinguisher; [ACGIH]

Comments

Liquid causes second degree burns after contact for a few minutes; [CHRIS] Corrosive to skin; [Quick CPC] "Methyl bromide is a neurotoxic gas that can cause convulsions, coma, and long-term neuromuscular and cognitive deficits. Exposure to high concentrations of pure methyl bromide may cause inflammation of the bronchi or lungs, an accumulation of fluid in the lung, and irritation of the eyes and nose." [ATSDR Medical Management] Methyl bromide causes liver injury in acute inhalation studies of laboratory animals. [ACGIH] Acts as an alkylating agent of glutathione and other cellular molecules; Poor warnig properties, so 2% chloropicrin often added; [Olson, p. 321-2] Effects on the CNS, kidneys, and lungs (possible lung edema after inhalation); [ICSC]

Restricted

Use was discontinued as a refrigerant and fire extinguisher because of hazards; [ACGIH] Being phased out as an ozone-depleting chemical: developed nations (2005); undeveloped nations (2015); Still being used in US; [Olson, p. 321]

Reference Link

ATSDR - ToxFAQs - Bromomethane

Exposure Assessment
Skin Designation (ACGIH)

Yes

TIH

Yes

TLV (ACGIH)

1 ppm

PEL (OSHA)

Ceiling(OSHA) = 20 ppm

MAK

1 ppm

IDLH (NIOSH)

250 ppm

Excerpts from Documentation for IDLHs

Other animal data: It has been reported that rats have survived an exposure to 2,600 ppm for 24 minutes [Irish et al. 1940]. . . .Human data: It has been stated that 220 ppm can be endured for several hours without serious effects [Clarke et al. 1945].

Odor Threshold Low

20 ppm

Odor Threshold High

1000 ppm

Lethal Concentration

LC50 (rat) = 302 ppm/8 hr

Explanatory Notes

Odor thresholds from CHEMINFO;

Half Life

Whole body: 16 days; [TDR, p. 842]

Reference Link

ATSDR Medical Management - Methyl bromide

Adverse Effects
Toxic Pneumonitis

Yes

Neurotoxin

Other CNS Neurotoxin

Hepatotoxin

Hepatotoxin, Secondary

Dermatotoxin

Skin Burns

IARC Carcinogen

Not Classifiable

ACGIH Carcinogen

Not Classifiable

Links to Other NLM Databases
Health Studies

Human Health Effects from Hazardous Substances Data Bank:

Toxicity Information

Search TOXNET

Chemical Information

Search ChemIDplus

Biomedical References

Search PubMed

Related Information in HazMap
Diseases

Occupational diseases associated with exposure to this agent:

Processes

Industrial Processes with risk of exposure: