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Chemical Sampling Information (CSI)
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General Description

Synonyms: Bromomethane

OSHA IMIS Code Number: 1680

Chemical Abstracts Service (CAS) Registry Number: 74-83-9

NIOSH Registry of Toxic Effects of Chemical Substances (RTECS) Identification Number: PA4900000

Department of Transportation Regulation Number (49 CFR 172.101) and Guide: 1062 123

NIOSH Pocket Guide to Chemical Hazards, Methyl bromide: chemical description, physical properties, potentially hazardous incompatibilities, and more

Exposure Limits

OSHA Permissible Exposure Limit (PEL):

General Industry: 29 CFR 1910.1000 Z-1 Table -- 20 ppm, 80 mg/m3 Ceiling; Skin

Construction Industry: 29 CFR 1926.55 Appendix A -- 20 ppm, 80 mg/m3 Ceiling; Skin

Maritime: 29 CFR 1915.1000 Table Z-Shipyards -- 20 ppm, 80 mg/m3 Ceiling; Skin

American Conference of Governmental Industrial Hygienists (ACGIH) Threshold Limit Value (TLV): 1 ppm TWA; Skin; Appendix A4 - Not classifiable as a Human Carcinogen

National Institute for Occupational Safety and Health (NIOSH) Recommended Exposure Limit (REL): Appendix A - NIOSH Potential Occupational Carcinogens

Health Factors

Carcinogenic Classification:

International Agency for Research on Cancer (IARC): Group 3, not classifiable as to its carcinogenicity to humans

NIOSH Immediately Dangerous To Life or Health Concentration (IDLH): 250 ppm

Potential Symptoms: Irritation, eyes, skin, respiratory system; blurred or double vision; slurred speech; dizziness; loss of appetite, nausea, vomiting, abdominal pain; headache; malaise; hand tremor; confusion; numbness of the arms and legs; paralysis; convulsions; unconsciousness; coughing, chest pain, dyspnea, pulmonary edema; oliguria, anuria, kidney hemorrhage; skin vesiculation (burns and blistering); frostbite, corneal burns (from liquid); (potential occupational carcinogen)

Health Effects: Cumulative nervous system (HE7) and organ damage (HE3); Acute toxicity (HE3) and lung edema (HE11).

Affected Organs: Nervous system, respiratory system, kidneys, skin, eyes


  1. Practically odorless with an odor threshold near, or greater than, the PEL.
  2. Convulsions may be resistant to anti-convulsant drug treatment and require prolonged drug-induced coma.
  3. Can be absorbed through the skin, and death has occurred by this route. Can also dissolve through ordinary rubber gloves and cause symptoms.
  4. Health effects of similar exposures may differ due to genetic differences in the ability to metabolize methyl bromide.
  5. Methyl bromide production and importation are being phased out under the Clean Air Act due to concerns about ozone depletion. Target date for 100% reduction is Jan. 1, 2005. Exempted are quarantine, preshipment, and critical agricultural uses.

Literature Basis:

  • NIOSH Pocket Guide to Chemical Hazards: Methyl bromide.
  • International Chemical Safety Cards (WHO/IPCS/ILO): Methyl Bromide.
  • EPA Air Toxics Website: Methyl Bromide (Bromomethane). U.S. Environmental Protection Agency Technology Transfer Network.
  • Garnier, R., Rambourg-Schepens, M.O., Muller, A. and Hallier, E.: Glutathione transferase activity and formation of macromolecular adducts in two cases of acute methyl bromide poisoning. Occup. Environ. Med. 53(3): 211-215, 1996.
  • Lenhart, S.W. and Gagnon, Y.T.: Health hazard evaluation of methyl bromide soil fumigations. Appl. Occup. Environ. Med. 14(7): 407-412, 1999.
  • No authors: Methyl bromide. IARC Monogr. Eval. Carcinog. Risks Hum. 71(Pt. 2): 721-735, 1999.
  • Pohanish, R.P. (editor): Methyl Bromide. In, Sittig's Handbook of Toxic and Hazardous Chemicals and Carcinogens, Fourth Ed., Vol. 2. Norwich, NY: Noyes Publications, William Andrew Publishing, 2002, pp. 1531-1534.

Date Last Revised: 01/06/2004

Monitoring Methods used by OSHA

Primary Laboratory Sampling/Analytical Method (SLC1):

  • sampling media: Two Anasorb 747 Tubes in series (400/200 mg sections) See Note
    analytical solvent: Carbon Disulfide
    maximum volume: 3 Liters
    maximum flow rate: 0.2 L/min
    current analytical method: Gas Chromatography; GC/FID
    method reference: OSHA Manual of Analytical Methods (OSHA PV2040)
    method classification: Partially Validated
    note: The Anasorb tubes should be separated and capped after sampling. Tubes should be refrigerated as soon after sampling as possible and shipped cold to the Salt Lake Technical Center. NIOSH Method 2520 [31 KB PDF, 5 pages] has problems with capacity as the humidity changes.

On-Site Sampling Techniques/Methods:

  • device: Detector Tube
    manufacturer: Gastec
    model/type: 136LA
    sampling information: 1 or 2 strokes
    upper measurement limit: 36 ppm
    detection limit: 0.2 ppm
    overall uncertainty: 16% for 1 to 6 ppm, 8% for 6 to 18 ppm
    method reference: on-site air secondary (SEI Certified)

  • device: Detector Tube
    manufacturer: Matheson-Kitagawa
    model/type: 8014-157SB
    sampling information: 1, 2 or 4 strokes
    upper measurement limit: 80 ppm
    detection limit: approximately 0.2 ppm
    overall uncertainty: unknown
    method reference: on-site air secondary (SEI Certified)

Wipe Sampling Method:

  • Wipe with charcoal pad, seal in glass vial for shipment.

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