An official website of the United States government
1,1,2-Trichloroethane
May 1994
Immediately Dangerous to Life or Health Concentrations (IDLH)
CAS number: 79–00–5
NIOSH REL: 10 ppm (45 mg/m3) TWA [skin]; NIOSH considers 1,1,2-trichloroethane to be a potential occupational carcinogen as defined by the OSHA carcinogen policy [29 CFR 1990].
Current OSHA PEL: 10 ppm (45 mg/m3) TWA [skin]
1989 OSHA PEL: Same as current PEL
1993-1994 ACGIH TLV: 10 ppm (55 mg/m3) TWA [skin]
Description of substance: Colorless liquid with a sweet, chloroform-like odor.
LEL: . . 6% (10% LEL, 6,000 ppm)
Original (SCP) IDLH: 500 ppm
Basis for original (SCP) IDLH: The chosen IDLH is based on the UCC [1972] report that 500 ppm killed 1 of 6 rats in 4 hours, and 4 of 6 rats in 8 hours.
Short-term exposure guidelines: None developed
ACUTE TOXICITY DATA:
Lethal concentration data:
| Species | Reference | LC50 | LCLo | Time | Adjusted 0.5-hrLC (CF) | Derived value |
|---|---|---|---|---|---|---|
| Cat | Arch Hyg Bakteriol 1936 | —– | 13,100 mg/m3 | 4.5 hr | 4,957 ppm (2.1) | 496 ppm |
| Rat | Carpenter et al. 1949 | —– | 2,000 ppm | 4 hr | 4,000 ppm (2.0) | 400 ppm |
| Rat | UCC 1972 | LC17: 500 ppm | —– | 4 hr | 1,000 ppm (2.0) | 100 ppm |
| Rat | UCC 1972 | LC67: 500 ppm | —– | 8 hr | 1,250 ppm (2.5) | 125 ppm |
Human data: None relevant for use in determining the revised IDLH.
| Revised IDLH: 100 ppm Basis for revised IDLH: The revised IDLH for 1,1,2-trichloroethane is 100 ppm based on acute inhalation toxicity data in animals [UCC 1972]. [Note: NIOSH recommends as part of its carcinogen policy that the “most protective” respirators be worn for 1,1,2-trichloroethane at concentrations above 10 ppm.] |
REFERENCES:
1. Arch Hyg Bakteriol [1936]; 116:131 (in German).
2. Carpenter CP, Smyth HF Jr, Pozzani UC [1949]. The assay of acute vapor toxicity and the grading and interpretation of results on 96 chemical compounds. J Ind Hyg Toxicol 31(6):343-346.
3. UCC [1972]. Toxicology studies: 1,1,2-trichloroethane. New York, NY: Union Carbide Corporation.