Mammalian Toxicity of 1,3-Dichloropropene

1,3-Dichloropropene (DCP) has primarily been employed for the control of parasitic nematodes for preplanting control of parasitic plant nematodes in numerous food and nonfood crops including deciduous fruit and nuts, vines, strawberries, field crops, vegetables, tobacco, tree nurseries, and numerous other specialty crops. Soil fumigant formulations have historically varied in DCP content from 50% to 97% purity as approximately equal amounts of cis- and trans-isomers to the more recent purified cis-only formulations. An acid scavenger, historically epichlorohydrin (Epi) or, more recently, epoxidized soybean oil (ESO), has been added to the final formulation at a concentration of l%–2%. In addition, DCP may be mixed with a variable amount of a disease control agent such as methylisothiocyanate or chloropicrin. Formulated DCP is typically injected into the soil where it subsequently dissolves into the film of water that surrounds soil particles and which harbors the targeted organism, parasitic nematodes. DCP in the soil is lost via chemical hydrolysis in water, metabolism by soil biotica, and volatilization. Half-lives in soil and water in the absence of volatilization typically range from 2 to 13 d, dependent upon temperature and microbial load (WHO 1993). Efficacy is thus dictated not only by target organism sensitivity but also by a number of physicochemical properties of DCP and soil and atmospheric conditions.