Immediately Dangerous to Life or Health Concentrations (IDLH)
CAS number: 75-25-2
NIOSH REL: 0.5 ppm (5 mg/m3) TWA [skin]
Current OSHA PEL: 0.5 ppm (5 mg/m3) TWA [skin]
1989 OSHA PEL: Same as current PEL
1993-1994 ACGIH TLV: 0.5 ppm (5.2 mg/m3) TWA [skin]
Description of substance: Colorless to yellow liquid with a chloroform-like odor.
LEL: Noncombustible Liquid
Original (SCP) IDLH: Unknown [*Note: “Effective” IDLH = 1,000 ppm — see discussion below.]
Basis for original (SCP) IDLH: Grant  reported that bromoform is a heavy liquid which resembles chloroform physically, chemically, and pharmacologically but is more toxic to the liver and more irritant on inhalation, causing tearing and salivation [Fairhall 1957]. AIHA  reported that a concentration of chloroform immediately dangerous to life or health has not been established, but that a concentration of 14,000 to 16,000 ppm will cause rapid loss of consciousness in man [Patty 1963]. Lower concentrations of chloroform (4,100 ppm or less) may cause disorientation serious enough to result in falls or other mechanical accidents [Patty 1963]. However, for this draft technical standard, respirators have been selected on the basis of the assigned protection factor afforded by each device up to 2,000 x the OSHA PEL of 0.5 ppm (i.e., 1,000 ppm); only the “most protective” respirators are permitted for use in concentrations exceeding 1,000 ppm.
Short-term exposure guidelines: None developed
ACUTE TOXICITY DATA
Lethal concentration data:
|Species||Reference||LC50(ppm)||LCLo(ppm)||Time||Adjusted 0.5-hr LC (CF)||Derived Value|
|Rat||Izmerov et al. 1982||-----||4,282||4 hr||8,564 ppm (2.0)||856 ppm|
|Mammal||Lublinov and Rabolnikova 1974||1,151 -----||?||?||?|
|Dog||Patty 1963||-----||7,000||1 hr||8,750 ppm (1.25)||875 ppm|
Lethal dose data:
|Species||Reference||Route||LD50(mg/kg)||LDLo(mg/kg)||Adjusted LD||Derived Value|
|Mouse||Bowman et al. 1978||oral||-----||1,400||932 ppm||93 ppm|
|Rat||Chu et al. 1980||oral||-----||1,147||764 ppm||76 ppm|
Human data: It has been reported that 14,000 to 16,000 ppm will cause rapid loss of consciousness [Patty 1963]. The reported lethal oral dose is 143 mg/kg [Deichmann and Gerarde 1969]. [Note: An oral dose of 143 mg/kg is equivalent to a 70-kg worker being exposed to about 635 ppm for 30 minutes, assuming a breathing rate of 50 liters per minute and 100% absorption.]
|Revised IDLH: 850 ppm
Basis for revised IDLH: The revised IDLH for bromoform is 850 ppm based on acute inhalation toxicity data in animals [Izmerov et al. 1982]. This may be a conservative value due to the lack of relevant acute toxicity data for workers exposed to concentrations between 850 and 14,000 ppm.
- AIHA . Bromoform. In: Hygienic guide series. Am Ind Hyg Assoc J 26:637.
- Bowman FJ, Borzellica JF, Munson AE . Short communication: the toxicity of some halomethanes in mice. Toxicol Appl Pharmacol 44:213-215.
- Chu I, Secours V, Marino I, Villeneuve DC . The acute toxicity of four trihalomethanes in male and female rats. Toxicol Appl Pharmacol 52:351-353.
- Deichmann WB, Gerarde HW . Bromoform. In: Toxicology of drugs and chemicals. New York, NY: Academy Press, Inc., pp. 141-142.
- Fairhall LT . Industrial toxicology. 2nd ed. Baltimore, MD: Williams & Wilkins Company, pp. 170-171.
- Grant WM . Toxicology of the eye. 2nd ed. Springfield, IL: C.C. Thomas, p. 203.
- Izmerov NF, Sanotsky IV, Sidorov KK . Toxicometric parameters of industrial toxic chemicals under single exposure. Moscow, Russia: Centre of International Projects, GKNT, p. 28.
- Lublinov ET, Rabolnikova LB . Acute toxicity data of some bromohydrocarbons. Gig Tr Prof Zabol 18(4):55-57 (in Russian).
- Patty FA, ed. . Industrial hygiene and toxicology. 2nd rev. ed. Vol. II. Toxicology. New York, NY: Interscience Publishers, Inc., p. 1261.