National Toxicology Program

CASRN: 74-83-9

Formula: C-H3-Br

Synonyms/Common Names:

• BROMOMETHANE (9CI)

Known Uses:

Fumigant, extractant, wool degreasing, in ion. Chambers, fire-extinguishing agent, insecticide, rodenticide. Associated with tobacco: reported either as a natural component of tobacco, pyrolysis product (in tobacco smoke), or additive for one or more types of tobacco products.

Short-Term Toxicity

• 14-Day (Inhalation)  (C04148A)  Completed 
  • Mice: B6C3F1
• 6 weeks (Inhalation)  (C04148C)  Completed 
  • Rats: F344/N; Mice: B6C3F1
• 13-Week (Inhalation)  (C04148A)  Completed 
  • Rats: F344/N; Mice: B6C3F1
  • Dose: R: 0,30,120, M: 0,10,120 PPM/10 PER GROUP.

Long-Term Carcinogenicity

• 2-YEAR (Inhalation)  (C04148B)  Report Complete 
  • TR-385 (NIH Number: 92-2840; NTIS Number: PB92-189257)  (Peer Review Approval 11/19/1990A )
    Toxicology and Carcinogenesis Studies of Methyl Bromide (CASRN 74-83-9) in B6C3F1 Mice (Inhalation Studies)
  • Mice: B6C3F1
  • Carcinogenesis Results
  • Male Mice No Evidence 
  • Female Mice No Evidence 
  • Dose: MICE ONLY:0,10,33,100 PPM.

Special Studies

• Absorption Disposition Metabolism Elimination (Gavage)  (S0165)  Completed 
  • Citation: MEDINSKY, M.A., ET.AL., DISPOSITION OF [14C] METHYL BROMIDE IN F344 RATS AFTER ORAL OR INTRAPERITONEAL ADMINISTRATION, TOXICOL 32:187-196, 1984.
  • Male Rats: F344/N
  • Dose: 250 MICROMOLES.
• Absorption Disposition Metabolism Elimination (Inhalation)  (S0335)  Completed 
  • Citation: DISPOSITION OF [14C]METHYL BROMIDE IN RATS AFTER INHALATION. BOND, ET AL. TOXICOLOGY AND APPLIED PHARMACOLOGY. 78:47-54, 1985. UPTAKE AND EXCRETION OF [14C]METHYL BROMIDE AS INFLUENCED BY EXPOSURE CONCENTRATION. MEDINSKY, ET AL., TOX. & APPL. PHARM. 78:215-228, 1985.
  • Male Rats: F344/N
  • Dose: 337 NANAMOLES/L FOR 6 HRS (1ST STUDY) 50, 300, 5700, 10,400 NANOMOLES FOR 6 HRS (2ND STUDY).

Genetic Toxicology

• Micronucleus  (A51339)  Completed 
  • Citation: Witt, K.L., Knapton, A., Wehr, C.M., Hook, G.J., Mirsalis, J., Shelby, M.D., and MacGregor, J.T. Micronucleated Erythrocyte Frequency in Peripheral Blood of B6C3F1 Mice from Short-Term, Prechronic, and Chronic Studies of the NTP Carcinogenesis Bioassay Program. Environ. Molec. Mutagen. Vol. 36 (2000) 163-194
  • Mice: B6C3F1
  • Male Positive 
  • Female Positive 
• Salmonella  (510898)  Completed 
  •  Positive 

Organ Systems Toxicity

• Neurotoxicology Assessment (Inhalation)  (NTA94006)  Completed 
  • Citation: Animal Neurobehavioral Test Battery in NTP Assessment In: Advances in Neurobehavioral Toxicology: Applications in Environmental & Occupational Health (Barry L. Johnson, ED.), Lewis Publishers, Inc. pp. 403-418 (1990).
  • Male and Female Rats/Mice: F344/N
• 5 days/week for 3 weeks before breeding, or 1 to 19 GD, or 3 weeks before breeding plus 1 to 19 GD Conventional Teratology (Inhalation)  (T0021A)  Completed 
  • NTIS Number: PB81-168510
    Citation: Teratologic Assessment of Butylene Oxide, Styrene Oxide, Methylbromide
  • Female Rats: Wistar
  • Dose: 20,70 PPM 7HR/D.
• 1 to 15 GD Conventional Teratology (Inhalation)  (T0021B)  Completed 
  • NTIS Number: PB81-168510
    Citation: Teratologic Assessment of Butylene Oxide, Styrene Oxide, Methylbromide
  • Female Rabbit: New Zealand White
  • Dose: 20 OR 70 PPM, 7HR/D.