1,3-Dichloropropene

1,3-Dichloropropene, sold under diverse trade names, is an organochlorine compound. It is colorless liquid with a sweet smell. It dissolves in water and evaporates easily. It is used mainly in farming as a pesticide, specifically as a preplant fumigant and nematicide. It is widely used in the US and other countries, but is in the process of being phased out in the European Union.
Production, chemical properties, biodegradation.
It is a byproduct in the chlorination of propene to make allyl chloride.
It is usually obtained as a mixture of the geometric isomers, called Z-1,3-dichloropropene, and E-1,3-dichloropropene. Although it was first applied in agriculture in the 1950s, at least two biodegradation pathways have evolved. One pathway degrades the chlorocarbon to acetaldehyde via chloroacrylic acid.
Safety.
The TLV-TWA for 1,3-dichloropropene (DCP) is 1 ppm. It is a contact irritant. A wide range of complications have been reported.
Carcinogenicity.
Evidence for the carcinogenicity of 1,3-dichloropropene in humans is inadequate, but results from several cancer bioassays provide adequate evidence of carcinogenicity in animals. In the US, the Department of Health and Human Services (DHHS) has determined that 1,3-dichloropropene may reasonably be anticipated to be a carcinogen. The International Agency for Research on Cancer (IARC) has determined that 1,3-dichloropropene is possibly carcinogenic to humans. The EPA has classified 1,3-dichloropropene as a probable human carcinogen.
Use.
1,3-Dichloropropene is used as a pesticide in the following crops: 
Contamination.
The ATSDR has extensive contamination information available.