Acetic anhydride
May 1994
Immediately Dangerous to Life or Health Concentrations (IDLH)
CAS number: 108-24-7
NIOSH REL: 5 ppm (20 mg/m3) CEILING
Current OSHA PEL: 5 ppm (20 mg/m3) TWA
1989 OSHA PEL: 5 ppm (20 mg/m3) CEILING
1993-1994 ACGIH TLV: 5 ppm (21 mg/m3) TWA
Description of substance: Colorless liquid with a strong, pungent, vinegar-like odor.
LEL: 2.7% (10% LEL, 2,700 ppm)
Original (SCP) IDLH: 1,000 ppm
Basis for original (SCP) IDLH: According to AIHA [1971], all rats exposed for 4 hours to 2,000 ppm were dead within 14 days while all rats exposed for 4 hours to 1,000 ppm survived the 14-day observation period [Capellini and Sartorelli 1967]. Because 2,000 ppm is obviously too high to be selected as the IDLH, 1,000 ppm has been chosen.
Short-term exposure guidelines: None developed
ACUTE TOXICITY DATA
Lethal concentration data:
| Adjusted | ||||||
|---|---|---|---|---|---|---|
| LC50 | LCLo | 0.5-hr | Derived | |||
| Species | Reference | (ppm) | (ppm) | Time | LC (CF) | Value |
| Rat | Deichmann and | 1,000 | ----- | 4 hr | 2,000 ppm (2.0) | 200 ppm |
Human data: None relevant for use in determining the revised IDLH.
Revised IDLH: 200 ppm Basis for revised IDLH: The revised IDLH for acetic anhydride is 200 ppm based on acute inhalation toxicity data in animals [Deichmann and Gerarde 1969]. This may be a conservative value due to the lack of relevant acute toxicity data for workers. |
References:
- AIHA [1972]. Acetic anhydride. In: Hygienic guide series. Am Ind Hyg Assoc J 32(1):64-67.
- Capellini A, Sartorelli [1967]. Episodio di intossicazione collettiva da anidride acetica ed acido acetico. Med Lav 58:108-112 (in Italian).
- Deichmann WB, Gerarde HW [1969]. Trifluoroacetic acid (3FA). In: Toxicology of drugs and chemicals. New York, NY: Academic Press, Inc., p. 607.