Methyl methacrylate
May 1994
Immediately Dangerous to Life or Health Concentrations (IDLH)
CAS number: 80–62–6
NIOSH REL: 100 ppm (410 mg/m3) TWA
Current OSHA PEL: 100 ppm (410 mg/m3) TWA
1989 OSHA PEL: Same as current PEL
1993-1994 ACGIH TLV: 100 ppm (410 mg/m3) TWA
Description of substance: Colorless liquid with an acrid, fruity odor.
LEL: . . . 1.7% (10% LEL, 1,700 ppm)
Original (SCP) IDLH: 4,000 ppm
Basis for original (SCP) IDLH: The chosen IDLH is based on the statement by ACGIH [1971] that 4,400 ppm was fatal to rats and rabbits in 8 hours [Deichmann 1941]. Also, Patty [1963] cited an approximate rat LC50 of 3,750 ppm [Deichmann 1941; Spealman et al. 1945].
Short-term exposure guidelines: None developed
ACUTE TOXICITY DATA:
Lethal concentration data:
| Species | Reference | LC50 (ppm) |
LCLo (ppm) |
Time | Adjusted 0.5-hr LC (CF) |
Derived value |
| Rat | Blagodatin et al. 1976 | 18,750 | ----- | 4 hr | 37,500 ppm (2.0) | 3,750 ppm |
| Mouse | Blagodatin et al. 1976 | 4,447 | ----- | 2 hr | 7,115 ppm (1.6) | 712 ppm |
| Rat | Deichmann 1941 | ----- | 4,400 | 8 hr | 11,000 ppm (2.5) | 1,100 ppm |
| Rabbit | Deichmann 1941 | ----- | 4,400 | 8 hr | 11,000 ppm (2.5) | 1,100 ppm |
| Rabbit | Deichmann 1941 | ----- | 4,207 | 4.5 hr | 8,751 ppm (2.08) | 875 ppm |
| G. pig | Deichmann 1941 | ----- | 4,567 | 5 hr | 9,819 ppm (2.15) | 982 ppm |
| Rat | Deichmann 1941 | 3,750 | ----- | ? | ? | ? |
| Mammal | Gig Sanit 1986 | 4,808 | ----- | ? | ? | ? |
Human data: Workers have experienced irritation, but tolerated 200 ppm without complaint [Spealman et al. 1945]. It has also been reported that 2,300 ppm was intolerable [Coleman 1963].
| Revised IDLH: 1,000 ppm Basis for revised IDLH: The revised IDLH for methyl methacrylate is 1,000 ppm based on acute inhalation toxicity data in humans [Coleman 1963] and animals [Blagodatin et al. 1976; Deichmann 1941]. |
REFERENCES:
1. ACGIH [1971]. Methyl methacrylate. In: Documentation of the threshold limit values for substances in workroom air. 3rd ed. Cincinnati, OH: American Conference of Governmental Industrial Hygienists, p. 168.
2. Blagodatin VM, Smiznova ES, et al. [1976]. Substantiation of the maximum permissible concentration of methacrylic acid methyl ether in the air of the working zone. Gig Tr Prof Zabol 20(6):5-8 (in Russian).
3. Coleman AL [1963]. Letter to the TLV Committee from State of Connecticut, Labor Department, Occupational Health Section (March 15, 1963).
4. Deichmann W [1941]. Toxicity of methyl, ethyl, and n-butyl methacrylate. J Ind Hyg Toxicol 23:343-351.
5. Gig Sanit [1986]; 51(5):61 (in Russian).
6. Patty FA, ed. [1963]. Industrial hygiene and toxicology. 2nd rev. ed. Vol. II. Toxicology. New York, NY: Interscience Publishers, Inc., p. 1880.
7. Spealman CR, Main RJ, Haag HB, Larson PS [1945]. Monomeric methyl methacrylate. Am J Ind Med 14(4):292-298.