Volatile dichloropropene

Dichloropropene is released into the air and in wastewater during its production and use as a soil fumigant and chemical intermediate. 1,3-Dichloropropene may also leach into groundwater. Considerable variation in the amounts of 1,3-dichloropropene lost by volatilization and degradation can be expected depending on the method of application, soil type, moisture and temperature. It has been detected in low levels in ambient air and drinking-water (United States National Library of Medicine, 1997). 

Figure 4. Simulated and measured 1,3-dichloropropene (1,3-D) volatilization flux in response to atmospheric pressure changes at Salinas Valley. Reprinted with permission from Chen et al. (1995). Copyright 1995, American Chemical Society...

Chen, C., Green, R. E., Thomas, D. M., and Knuteson, J. A. (1995). Modeling 1,3-dichloropropene fumigant volatilization with vapor-phase advection in the soil profile. Environmental Science and Technology, 29(7), 1816-1821. 

Dichloropropene is mobile and persistent, particularly in colder climates. When injected into the soil, its mobility is controlled by temperature, soil type, and moisture. Even though volatilization occurs from the soil surface, most 1,3-dichloropropene is degraded through hydrolysis to 3-dichloroallyl alcohol. The overall half-life of the compound in soil ranges from a few days to more than 9 weeks depending on conditions. Adsorption to sediment and bioconcentration in fish are not important processes. 

One mode of control of nematodes living in the soil is the application of volatile soil fumigants, the vapours of which attain in the air space of the soil a concentration sufficient to Icill them. The major part of these substances can be classified among the aliphatic chlorinated hydrocarbons. Their action is aspecihc, so that they cannot be used during the active vegetative period because they damage plants. Their most important representatives are bromomethane (1), 1,2-di-bromoethane (2), a mixture of 1,3-dichloropropene (3) and 1,2-dichloropropane... 

Wang, D. Yates, S. R. Ernst, F. F. Knuteson, J. A. Volatilization of 1,3-dichloropropene under different application methods. Water, Air, Soil Pollut, 2001,127, 109-123. 

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