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Acetylene tetrabromide

May 1994
Immediately Dangerous to Life or Health Concentrations (IDLH)

CAS number: 79-27-6

NIOSH REL: The 1989 OSHA PEL may not be protective to workers.

Current OSHA PEL: 1 ppm (14 mg/m3) TWA

1989 OSHA PEL: Same as current PEL

1993-1994 ACGIH TLV: 1 ppm (14 mg/m3) TWA

Description of substance: Pale-yellow liquid with a pungent odor similar to camphor or iodoform.

LEL: Noncombustible Liquid

Original (SCP) IDLH: 10 ppm

Basis for original (SCP) IDLH: Van Haaften [1969] reported that a chemist who had been exposed to 1 to 2 ppm for 7.5 hours, with only a single 10-minute exposure at 16 ppm, almost died from liver damage. Because the TLV is 1 ppm [ACGIH 1976], it is assumed that exposure to 1 to 2 ppm would be a safe concentration for the 7.5 hours the worker was exposed. Therefore, the injury must have been produced by the 10-minute exposure to 16 ppm, and the IDLH would be expected to fall between 2 ppm and 15 ppm. For this draft technical standard, an IDLH of 10 ppm is assumed. This is an extremely toxic substance.

Short-term exposure guidelines: None developed


Lethal concentration data:

Species Reference LC50(ppm) LCLo(ppm) Time Adjusted 0.5-hr LC (CF) Derived Value
Rat Izmerov et al. 1982 38 —– 4 hr 76 ppm (2.0) 7.6 ppm

Lethal dose data:

Species Reference Route LD50(mg/kg) LDLo(mg/kg) Adjusted LD Derived Value
G. pig Gray 1950 oral 400 —– 195 ppm 20 ppm
Rabbit Gray 1950 oral 400 —– 195 ppm 20 ppm
Mouse Izmerov et al.1982 oral 269 —– 131 ppm 13 ppm
Rat Paustovskaya et al. 1967 oral 1,200 —– 585 ppm 59 ppm

Human data: Severe acute intoxication was reported in a chemist after exposure to 16 ppm for about 10 minutes and to 1 to 2 ppm for most of the day [Van Haaften 1969].


  1. ACGIH [1976]. TLVs, Threshold limit values for chemical substances and physical agents in the workroom environment with intended changes for 1976. Cincinnati, OH: American Conference of Governmental Industrial Hygienists, p. 9.
  2. Gray MG [1950]. Effect of exposure to the vapors of tetrabromoethane (acetylene tetrabromide). AMA Arch Ind Hyg Occup Med 2:407-419.
  3. Izmerov NF, Sanotsky IV, Sidorov KK [1982]. Toxicometric parameters of industrial toxic chemicals under single exposure. Moscow, Russia: Centre of International Projects, GKNT, p. 107.
  4. Paustovskaya VV, et al. [1967]. Effect of tetrabromomethane on the parenchymatous organs in experimental conditions. Med Pr 3:80-83 (in Polish).
  5. Van Haaften AB [1969]. Acute tetrabromoethane (acetylene tetrabromide) intoxication in man. Am Ind Hyg Assoc J 30:251-256.