Acetic acid

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

ACUTE TOXICITY DATA

Lethal concentration data:

                                                       Adjusted               
                             LC50    LCLo               0.5-hr         Derived
Species     Reference       (ppm)   (ppm)    Time       LC (CF)         Value
______________________________________________________________________________
Mouse    Ghiringhelli and   5,620   -----    1 hr   7,025 ppm (1.25)   703 ppm
         DiFabio 1957
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].

REFERENCES:

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.