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Methyl acrylate

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

CAS number: 96–33–3

NIOSH REL: 10 ppm (35 mg/m3) TWA [skin]

Current OSHA PEL: 10 ppm (35 mg/m3) TWA [skin]

1989 OSHA PEL: Same as current PEL

1993-1994 ACGIH TLV: 10 ppm (35 mg/m3) TWA [skin]

Description of substance: Colorless liquid with an acrid odor.

LEL: . . 2.8% (10% LEL, 2,800 ppm)

Original (SCP) IDLH: 1,000 ppm

Basis for original (SCP) IDLH: The chosen IDLH is based on the rat 4-hour LC50 of 1,000 ppm in which 3 of 6 rats died [Smyth and Carpenter 1948 cited by Patty 1963].

Short-term exposure guidelines: None developed


Lethal concentration data:

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



Lomonova & Klimova 1979Oberly &Tansey 1985

Smyth &Carpenter 1948

Treon et al. 1949







?4 hr

4 hr

1 hr

?2,700 ppm (2.0)

2,000 ppm (2.0)

3,153 ppm (1.25)

?270 ppm

200 ppm

315 ppm

Other animal data: Rats exposed 4 hours per day, 5 days per week at 110 ppm for a total of 32 exposures had eye discomfort at the start of the investigation, but no overt signs of respiratory distress or other manifestations of toxicity were recorded [Oberly and Tansey 1985].

Human data: None relevant for use in determining the revised IDLH.


1. Lomonova GV, Klimova EI [1979]. On the toxicity methyl and ethyl acrylates. Gig Tr Prof Zabol 23(9):55-56 (in Russian).

2. Oberly R, Tansey MF [1985]. LC50 values for rats acutely exposed to vapors of acrylic and methacrylic acid esters. J Toxicol Environ Health 16:811-822.

3. Patty FA, ed. [1963]. Industrial hygiene and toxicology. 2nd rev. ed. Vol. II. Toxicology. New York, NY: Interscience Publishers, Inc., p. 1880.

4. Smyth HF Jr, Carpenter CP [1948]. Further experience with the range-finding test in the industrial toxicology laboratory. J Ind Hyg Toxicol 30:63-68.

5. Treon JF, Sigmon H, Wright H, Kitzmiller KV [1949]. The toxicity of methyl and ethyl acrylate. J Ind Hyg Toxicol 31:317-326.