1,3-Dichloropropene is a colorless liquid with a sweet smell. It exists as a mixture of the geometric isomers cis-1,3-dichloropropene and trans-1,3-dichloropropene. It dissolves in water and evaporates easily. It is used mainly in farming as a pesticide, specifically as a preplant fumigant and nematicide. It widely used in the US and other countries, but in the process of being phased out in the European Union.

Effects

1,3-Dichloropropene (DCP) causes irritation at the point of contact. Inhalation can cause nausea, vomiting, irritation of the skin, eyes, and throat; breathing difficulties, headache, and fatigue. These effects generally occur at exposure levels that are much higher than the background levels found in air or water. Rats and mice that inhaled DCP repeatedly for about 2 weeks had damage to the lining of the nose, and mice had damage to the lung.

A man who accidentally ingested DCP died with severe damage to his stomach and surrounding organs, but little else is known about the effects of ingesting these substances in humans. Animal studies have reported damage to the stomach lining, lung congestion, difficulty walking, and effects on the liver and kidneys from ingesting high levels of DCP.

A few workers who had skin contact with pesticides containing DCP developed blisters and an allergic reaction on their skin.

It is not known whether DCP can cause birth defects in humans. Pregnant rats that inhaled 1,3-dichloropropene gave birth to fewer pups or pups with lower body weight. This occurred at exposures high enough to be toxic to the mothers.

DCP is testable via blood and urine tests, although it is only detectable in the body for 1-2 after exposure. Exposure level estimates are possible with a blood sample.

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. 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:

1,3-Dichloropropene Use in Crops

Crop	Pounds (lb)	Primary Pesticide?
Tobacco	12,114,887	Yes
Potatoes	12,044,736	Yes
Sugar Beets	5,799,613	Yes
Cotton	3,735,543	Yes
Peanuts	3,463,003	Yes
Sweet Potatoes	1,210,872	Yes
Onions	674,183	Yes
Carrots	531,752	Yes
Watermelons	133,801	No
Cantaloups	121,395	No
Cucumbers	76,735	No
Strawberries	71,753	No
Sweet Peppers	28,247	No
Melons	12,471	No
Blueberries	3,090	No
Asparagus	1,105	No

Contamination

The ATSDR has extensive contamination information available.

References

• ATSDR ToxFAQs: Dichloropropenes
• ATSDR ToxFAQs: Dichloropropenes
• USGS Pesticide National Synthesis Project - Crop & Compound
• ATSDR Toxicological Profile (9.2 MB)

Further reading

• ATSDR Toxicological Profile (9.2 MB)