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Methyl acetate

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

CAS number: 79–20–9

NIOSH REL: 200 ppm (610 mg/m3) TWA, 250 ppm (760 mg/m3) STEL

Current OSHA PEL: 200 ppm (610 mg/m3) TWA

1989 OSHA PEL: 200 ppm (610 mg/m3) TWA, 250 ppm (760 mg/m3) STEL

1993-1994 ACGIH TLV: 200 ppm (606 mg/m3) TWA, 250 ppm (757 mg/m3) STEL

Description of substance: Colorless liquid with a fragrant, fruity odor.

LEL:. . 3.1% (10% LEL, 3,100 ppm)

Original (SCP) IDLH: 10,000 ppm

Basis for original (SCP) IDLH: The chosen IDLH is based on an analogy with butyl acetate and ethyl acetate which have IDLHs of 10,000 ppm.

Short-term exposure guidelines: None developed


Lethal concentration data:

Species Reference LC50 (ppm) LCLo (ppm) Time Adjusted 0.5-hr LC (CF) Derived value


Flury and Wirth 1933Flury and Wirth 1933

Smyth et al. 1962





4 hr1 hr

4 hr

22,078 ppm (2.0)27,191 ppm (1.25)

64,000 ppm (2.0)

2,208 ppm2,719 ppm

6,400 ppm

Lethal dose data:

Species Reference Route LD50 (mg/kg) LDLo (mg/kg) Adjusted LD Derived value
Rabbit Munch 1972 oral 3,700 —– 8,409 ppm 841 ppm

Human data: It has been reported that concentrations of 10,000 ppm for a short time caused irritation which persisted after exposure stopped [Clayton and Clayton 1981].


1. Clayton GD, Clayton FE, eds. [1981]. Patty’s industrial hygiene and toxicology. 3rd rev. ed. Vol. 2A. Toxicology. New York, NY: John Wiley & Sons, Inc., p. 2272.

2. Flury F, Wirth W [1933]. Zur toxikologie der lösungsmittel (Verschieden ester, aceton, methylalkohol). Arch Gewerbepath Gewerbehyg 5:1-90 (in German).

3. Munch JC [1972]. Aliphatic alcohols and alkyl esters: narcotic and lethal potencies to tadpoles and to rabbits. Ind Med Surg 41:31-33.

4. Smyth HF Jr, Carpenter CP, Weil CS, Pozzani UC, Striegel JA [1962]. Range-finding toxicity data: list VI. Am Ind Hyg Assoc J 23:95-107.