Immediately Dangerous to Life or Health Concentrations (IDLH)
CAS number: 75–34–3
NIOSH REL: 100 ppm (400 mg/m3) TWA
Current OSHA PEL: 100 ppm (400 mg/m3) TWA
1989 OSHA PEL: Same as current PEL
1993-1994 ACGIH TLV: 100 ppm (400 mg/m3) TWA
Description of Substance: Colorless, oily liquid with a chloroform-like odor.
LEL:. . 5.4% (10% LEL, 5,400 ppm)
Original (SCP) IDLH: 4,000 ppm
Basis for original (SCP) IDLH: Patty  reported that rats survived 8-hour exposures to 4,000 ppm, but died at 16,000 ppm [Smyth 1956]. However, 16,000 ppm has not been chosen as the IDLH because Kirk-Othmer  indicated that 1,1-dichloroethane causes narcosis. For this draft technical standard, 4,000 ppm is chosen as the IDLH.
Short-term exposure guidelines: None developed
ACUTE TOXICITY DATA
Lethal concentration data:
|Adjusted 0.5-hr |
|Carpenter et al. 1949 |
|4 hr |
|32,000 ppm (2.0) |
27,680 ppm (1.6)
40,000 ppm (2.5)
|3,200 ppm |
Human data: None relevant for use in determining the revised IDLH.
|Revised IDLH: 3,000 ppm |
Basis for revised IDLH: The revised IDLH for 1,1-dichloroethane is 3,000 ppm based on acute inhalation toxicity data in animals [Carpenter et al. 1949; Mueller 1925].
1. Carpenter CP, Smyth HF Jr, Pozzani UC . The assay of acute vapor toxicity, and the grading and interpretation of results on 96 chemical compounds. J Ind Hyg Toxicol 31:343-346.
2. Kirk-Othmer . Encyclopedia of chemical technology. 2nd ed. New York, NY: John Wiley & Sons, Inc. 5:92-98.
3. Mueller J . Comparative investigations on the anesthetic and toxic effects of some halogenated hydrocarbons. Arch Exp Pathol Pharmakol 109:276-294 (in German). [From ACGIH . 1,1-Dichloroethane. In: Documentation of the threshold limit values and biological exposure indices. 6th ed. Cincinnati, OH: American Conference of Governmental Industrial Hygienists, pp. 425-428.]
4. Patty FA, ed. . Industrial hygiene and toxicology. 2nd rev. ed. Vol. II. Toxicology. New York, NY: Interscience Publishers, Inc., pp. 1279-1280.
5. Smyth HF Jr . Improved communication: hygienic standards for daily inhalation. Am Ind Hyg Assoc Q 17(2):129-185.
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