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Acetic acid

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

CAS number: 64-19-7

NIOSH REL: 10 ppm (25 mg/m3) TWA, 15 ppm (37 mg/m3) STEL

Current OSHA PEL: 10 ppm (25 mg/m3) TWA

1989 OSHA PEL: Same as current PEL

1993-1994 ACGIH TLV: 10 ppm (25 mg/m3) TWA, 15 ppm (37 mg/m3) STEL

Description of substance: Colorless liquid or crystals with a sour, vinegar-like odor.

LEL: 4.0% (10% LEL, 4,000 ppm)

Original (SCP) IDLH: 1,000 ppm

Basis for original (SCP) IDLH: The chosen IDLH is based on the statement by Patty [1963] that Ghiringhelli and DiFabio [1957] determined a 1-hour LC50 of about 5,000 ppm for guinea pigs and mice. AIHA [1972] reported that 1 of 6 rats died following a 4-hour exposure to 16,000 ppm [Smyth et al. 1951]. However, the Standards Completion Program Respirator Committee felt that a worker might have difficulty escaping from 5,000 ppm due to the irritation effects, and reduced the IDLH to 1,000 ppm to allow escape without injury. According to AIHA [1972], workers have repeatedly sustained exposures up to about 200 ppm.

Short-term exposure guidelines: None developed


Lethal concentration data:
LC50 LCLo 0.5-hr Derived
Species Reference (ppm) (ppm) Time LC (CF) Value
Mouse Ghiringhelli and DiFabio 1957 5,620 ----- 1 hr 7,025 ppm (1.25) 703 ppm
Rat Smyth 1956 16,000 ----- 4 hr 32,000 ppm (2.0) 3,200 ppm

Other animal data: RD50 (mouse), 163 ppm [DeCeaurriz et al. 1981].

Human data: Marked irritation of the eyes, nose, and upper respiratory tract which could not be tolerated for more than 3 minutes was noted at 816 to 1,226 ppm [von Oettingen 1960]. It has been reported that 50 ppm or more is intolerable to most persons due to intense lacrimation and irritation of the eyes, nose, and throat [AIHA]. It has also been stated that repeated exposures to high concentrations may produce respiratory tract irritation with pharyngeal edema and chronic bronchitis [AIHA 1972].

Revised IDLH: 50 ppm

Basis for revised IDLH: The revised IDLH for acetic acid is 50 ppm based on acute inhalation toxicity data in humans [AIHA 1972].


  1. AIHA [1972]. Acetic acid. In: Hygienic guide series. Am Ind Hyg Assoc J 33:624-627.
  2. DeCeaurriz JC, Micillino JC, Bonnet P, Guenier JP [1981]. Sensory irritation caused by various industrial airborne chemicals. Toxicol Lett 9(2):137-143.
  3. Ghiringhelli L, DiFabio A [1957]. Pathology due to acetic acid: observations on experimental animals and man. Med Lav 48(10):560-561 (in Italian).
  4. Patty FA, ed. [1963]. Industrial hygiene and toxicology. 2nd rev. ed. Vol. II. Toxicology. New York, NY: Interscience Publishers, Inc., p. 1779.
  5. Smyth HF Jr [1956]. Improved communication: hygienic standards for daily inhalation. Am Ind Hyg Assoc Q 17:129-185.
  6. Smyth HF Jr, Carpenter CP, Weil CS [1951]. Range-finding toxicity data: list IV. AMA Arch Ind Hyg Occup Med 4:119-122.
  7. von Oettingen WF [1960]. The aliphatic acids and their esters: toxicity and potential dangers. AMA Arch Ind Health 21:40/28-77/65.