Acetylene tetrabromide

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

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	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].

Revised IDLH: 8 ppm Basis for revised IDLH: The revised IDLH for acetylene tetrabromide is 8 ppm based on acute inhalation toxicity data in animals [Izmerov et al. 1982].

REFERENCES:

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.