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 [1974] 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 [1965] 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. |
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