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Methyl formate

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

CAS number: 107–31–3

NIOSH REL: 100 ppm (250 mg/m3) TWA, 150 ppm (375 mg/m3) STEL

Current OSHA PEL: 100 ppm (250 mg/m3) TWA

1989 OSHA PEL: 100 ppm (250 mg/m3) TWA, 150 ppm (375 mg/m3) STEL

1993-1994 ACGIH TLV: 100 ppm (246 mg/m3) TWA, 150 ppm (368 mg/m3) STEL

Description of substance: Colorless liquid with a pleasant odor.

LEL: . . . 4.5% (10% LEL, 4,500 ppm)

Original (SCP) IDLH: 5,000 ppm

Basis for original (SCP) IDLH: The chosen IDLH is based on the

statement by ACGIH [1971] that 5,000 ppm was considered the maximum concentration guinea pigs could tolerate for 60 minutes without serious disturbances [Schrenk et al. 1936].

Short-term exposure guidelines: None developed

ACUTE TOXICITY DATA:

Lethal concentration data:

Species Reference LC50 (ppm) LCLo (ppm) Time Adjusted 0.5-hrLC (CF) Derived value
G. pig Schrenk et al. 1936 —– 50,000 20 min 43,500 ppm (0.87) 4,350 ppm

Lethal dose data:

Species Reference Route LD50 (mg/kg) LDLo (mg/kg) Adjusted LD Derived value
Rabbit Munch 1972 oral 1,622 —– 4,542 ppm 454 ppm

Other animal data: It has been stated that 5,000 ppm was considered the maximum concentration that guinea pigs could tolerate for 60 minutes without serious disturbances [Schrenk et al. 1936].

Human data: No adverse effects were found in humans after exposure to 1,500 ppm for 1 minute [Schrenk et al. 1936].

REFERENCES:

1. ACGIH [1971]. Methyl formate. In: Documentation of the threshold limit values for substances in workroom air. 3rd ed. Cincinnati, OH: American Conference of Governmental Industrial Hygienists, pp. 165-166.

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

3. Schrenk HH, Yant WP, Chornyak J, Patty FA [1936]. Acute response of guinea pigs to vapors of some new commercial organic compounds. XIII. Methylformate. Public Health Rep 51:1329-1335.