Agent Name

1,2-Dichloroethylene, all isomers

Alternative Name

Acetylene dichloride

CAS Number

540-59-0; 156-59-2; 156-60-5



Major Category



cis-Acetylene dichloride; trans-Acetylene dichloride; sym-Dichloroethylene; [NIOSH] 1,2-Dichloroethene; Dioform; [ChemIDplus] UN1150


Chlorinated Aliphatics


Colorless liquid (usually a mixture of the cis & trans isomers) with a slightly acrid, chloroform-like odor; [NIOSH]


Used as a solvent and chemical intermediate; [ACGIH] Used as a refrigerant, degreaser, dry cleaning agent, and solvent for perfumes, adhesives, lacquers, oils, and resins; [HSDB] Only the trans isomer is commercially available in the US--used for precision cleaning of electronic components and a small amount used as a blowing agent for specialty foams; [EPA Toxicological Review, 2010]


Liver injury observed in acute animal toxicology studies; [ACGIH] A skin, eye, and respiratory tract irritant; Inhalation of high concentrations may cause CNS effects; [ICSC]1,2-Dichloroethylene (UN1150) has warning of explosive polymerization; [ERG 2016] See "trans-1,2-Dichloroethylene" and "cis-1,2-Dichloroethylene."

Exposure Assessment
Skin Designation (ACGIH)

Insufficient data


200 ppm


200 ppm


200 ppm


1000 ppm

Excerpts from Documentation for IDLHs

Basis for original (SCP) IDLH: Patty [1963] reported that rats exposed to the cisisomer 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 transisomer was twice as toxic an anesthetic as the cisisomer, an IDLH of 4,000 ppm is chosen. . . . Human data: It has been reported that exposure to the transisomer at 2,200 ppm caused burning of the eyes, vertigo, and nausea [von Oettingen 1955]. An exposure to the transisomer 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].

Vapor Pressure

201 mm Hg

Odor Threshold Low

0.08 ppm

Odor Threshold High

17 ppm

Lethal Concentration

LC50 (mice) = 21,723 ppm/6H (trans-isomer);

Explosive Polymerization


Explanatory Notes

Odor threshold from "Quick Guide: The Electronic NIOSH Pocket Guide to Chemical Hazards"; VP = 180-265 mm Hg; Flash point = 2 deg C;

Reference Link

ATSDR - ToxFAQs - 1,2-Dichloroethene

Adverse Effects

CNS Solvent Syndrome


Hepatotoxin, Secondary

Links to Other NLM Databases
Health Studies

Human Health Effects from Hazardous Substances Data Bank:

Toxicity Information


Chemical Information

Search ChemIDplus

Related Information in HazMap

Occupational diseases associated with exposure to this agent:


Industrial Processes with risk of exposure: