1,2-Dichloroethylene

CAS number: 540–59–0

NIOSH REL: 200 ppm (790 mg/m³) TWA

Current OSHA PEL: 200 ppm (790 mg/m³) TWA

1989 OSHA PEL: Same as current PEL

1993-1994 ACGIH TLV: 200 ppm (790 mg/m³) TWA

Description of Substance: Colorless liquid (usually a mixture of the cis & trans isomers) with a slightly acrid, chloroform-like odor.

LEL:. . 5.6% (10% LEL, 5,600 ppm)

Original (SCP) IDLH: 4,000 ppm

Basis for original (SCP) IDLH: Patty [1963] reported that rats exposed to the cis-isomer of dichloroethylene for 4 hours at 8,000 ppm were neither killed nor anesthetized, but at 16,000 ppm, anesthesia occurred in 8 minutes and death occurred in 4 hours [Smyth 1956]. Because Patty [1963] also reported that the trans-isomer was twice as toxic and anesthetic as the cis-isomer, an IDLH of 4,000 ppm is chosen.

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
trans-isomer Mouse	ATSDR 1990	21,723	-----	6 hr	130,338 ppm (2.3)	13,034 ppm
cis-isomer Rat	Smyth 1956	-----	16,000	6 hr	32,000 ppm (2.0)	3,200 ppm

Lethal dose data:

Species	Reference	Route	LD50 (mg/kg)	LDLo (mg/kg)	Adjusted LD	Derived value
Rat	USDA 1966	oral	770	-----	1,337 ppm	134 ppm
trans-isomer Rat	Freudt et al. 1977	oral	1,275	-----	8,925 ppm	893 ppm

Human data: It has been reported that exposure to the trans-isomer at 2,200 ppm caused burning of the eyes, vertigo, and nausea [von Oettingen 1955]. An exposure to the trans-isomer at 819 ppm for 30 minutes has been reported to cause no untoward effects, while inhalation of either 1,687 to 2,184 ppm for 5 minutes or 1,191 ppm for 10 minutes has resulted in vertigo, pressure in the head, and somnolence [von Oettingen 1937].

Revised IDLH: 1,000 ppm Basis for revised IDLH: The revised IDLH for 1,2-dichloroethylene is 1,000 ppm based on acute inhalation toxicity data in humans [von Oettingen 1937, 1955].

REFERENCES:

1. ATSDR [1990]. Toxicological profile for 1,2-dichloroethene. Atlanta, GA: U.S. Department of Health and Human Services, Public Health Service, Agency for Toxic Substances and Disease Registry. ATSDR/TP-90-13, pp. 9-52.

2. Freudt KJ, Liebaldt GP, Lieberwirth E [1977]. Toxicity studies on trans-1,2-dichloroethylene. Toxicology 7:141-153.

3. Patty FA, ed. [1963]. Industrial hygiene and toxicology. 2nd rev. ed. Vol. II. Toxicology. New York, NY: Interscience Publishers, Inc., p. 1308.

4. Smyth HF Jr [1956]. Improved communication: hygienic standards for daily inhalation. Am Ind Hyg Assoc Q 17(2):129-185.

5. USDA [1966]. Informative memo no. 20. Beltsville, MD: U.S. Department of Agriculture, Agricultural Research Service, Entomology Research Division, Pesticide Chemicals Research Branch, p. 10.

6. von Oettingen WF [1937]. The halogenated hydrocarbons: their toxicity and potential dangers. J Ind Hyg Toxicol 19(8):409-411.

7. von Oettingen WF [1955]. The halogenated hydrocarbons, toxicity and potential dangers. Washington, DC: U.S. Public Health Service Publication No. 414, p. 199. [From ACGIH [1991]. 1,2-Dichloroethylene. In: Documentation of the threshold limit values and biological exposure indices. 6th ed. Cincinnati, OH: American Conference of Governmental Industrial Hygienists, pp. 429-431.]