Higher-tier assessment of the potential for groundwater issues due to the use of 1,3-D soil fumigant; evaluation of the active ingredient, metabolites and potentially related chlorinated compounds

Abstract

BACKGROUND: 1,3-Dichloropropene (1,3-D, CAS No. 542-75-6) is a broad-spectrum soil fumigant used to control numerous species of soilborne plant-parasitic nematodes. 1,3-D consists of two isomers, (Z)- and (E)-1,3-D. There are a number of low-level chlorinated compounds that could potentially be produced as a part of the 1,3-D manufacturing process. 1,3-D and its metabolites, as well as potentially related chlorinated compounds, represent potential groundwater contaminants. RESULTS: This study has investigated the hydrolytic stability, under biotic and abiotic conditions in the laboratory, of an extensive representative list of 1,3-D and potentially related chlorinated compounds in order to predict their environmental fate. All of these compounds showed intrinsic hydrolytic instability under both abiotic and biotic test conditions. Furthermore, a monitoring programme was carried out. Twenty-five wells were monitored in five Italian regions characterised by historical and existing use of 1,3-D. The parent compound, its two major metabolites and potentially related chlorinated compounds were not detected in the well water at > 0.1 μg L -1 at any sampling location. CONCLUSION: The soil fumigant (E,Z)-1,3-D, its metabolites and potentially related chlorinated compounds constitute a low risk to groundwater. © 2011 Society of Chemical IndustrY.