CARBON-14-TRIFLURALIN RESIDUES IN SOIL AND CARROTS

摘要

The persistence and movement of ~(14)C-trifluralin and its metabolites were studied in sandy loam soil under outdoor conditions. Uptake by carrots of the herbicide from the treated soil was also investigated. The bulk of the ~(14)C residues was present in the upper 0-7.5 cm layer during the growing period. The non-extractable ~(14)C residues increased with time. Downward movement of the ~(14)C-trifluralin, or its degradation products, was not observed at significant concentrations. After 4 months, 2.7 and 6.1% of the initially applied radioactivity were found in the form of metabolites, designated TR-1 and TR-2, respectively, in the combined soil samples from the three depths. The metabolites TR-4 and TR-1, as well as trace amounts of the metabolite TR-21, were present in the form of soil bound ~(14)C residues. Most of the radioactivity was located in the peel of the carrots. The pulp contained ~(14)C residues of TR-1 and TR-2 (0.010 and 0.004 ppm, respectively).