Immediately Dangerous to Life or Health Concentrations (IDLH)
CAS number: 109–94–4
NIOSH REL: 100 ppm (300 mg/m3) TWA
Current OSHA PEL: 100 ppm (300 mg/m3) TWA
1989 OSHA PEL: Same as current PEL
1993-1994 ACGIH TLV: 100 ppm (303 mg/m3) TWA
Description of Substance: Colorless liquid with a fruity odor.
LEL:. . 2.8% (10% LEL, 2,800 ppm)
Original (SCP) IDLH: 8,000 ppm
Basis for original (SCP) IDLH: The chosen IDLH is based on the statements by Smyth  cited in Patty  and by UCC  that 5 of 6 rats died following a 4-hour exposure to 8,000 ppm and no rats died from a 4-hour exposure to 4,000 ppm.
Short-term exposure guidelines: None developed
ACUTE TOXICITY DATA
Lethal concentration data:
|Adjusted 0.5-hr |
|Flury and Zernik 1931 |
Smyth et al. 1954
|1.5 hr |
|14,500 ppm (1.45) |
16,000 ppm (2.0)
16,000 ppm (2.0)
|1,450 ppm |
Lethal dose data:
|Jenner et al. 1964 |
Jenner et al. 1964
|4,205 ppm |
|421 ppm |
Other animal data: It has been stated that rats have survived a 4-hour exposure to 4,000 ppm [UCC 1968].
Human data: It has been reported that 330 ppm produced slight eye irritation and rapidly increasing nasal irritation [Flury and Zernik 1931].
|Revised IDLH: 1,500 ppm |
Basis for revised IDLH: The revised IDLH for ethyl formate is 1,500 ppm based on acute inhalation toxicity data in animals [Flury and Zernik 1931; Smyth 1956; Smyth et al. 1954]. This may be a conservative value due to the lack of relevant acute toxicity data for workers at concentrations above 330 ppm.
1. Flury F, Zernik F . Schädliche gase dämpfe, nebel, rauch- und staubarten. Berlin, Germany: Verlag von Julius Springer, p. 375 (in German).
2. Jenner PM, Hagan EC, Taylor JM, Cook EL, Fitzhugh OG . Food flavourings and compounds of related structure. I. Acute oral toxicity. Food Cosmet Toxicol 2:327-343.
3. Munch JC . Aliphatic alcohols and alkyl esters: narcotic and lethal potencies to tadpoles and to rabbits. Ind Med Surg 41:31-33.
4. Patty FA, ed. . Industrial hygiene and toxicology. 2nd rev. ed. Vol. II. Toxicology. New York, NY: Interscience Publishers, Inc., p. 1855.
5. Smyth HF Jr . Improved communication: hygienic standards for daily inhalation. Am Ind Hyg Assoc Q 17(2):129-185.
6. Smyth HF Jr, Carpenter CP, Weil CS, Pozzani UC . Range-finding toxicity data: list V. AMA Arch Ind Hyg Occup Med 10:61-68.
7. UCC . Toxicology studies: ethyl formate. New York, NY: Union Carbide Corporation.
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