Fate of a sulfonylurea herbicide in an alluvial soil, as shown by experimental degradation of pyrimidine-2-14C-labeled rimsulfuron

The distribution of Pyrimidine-2-14C-labeled rimsulfuron applied to a sandy calcareous alluvial soil, among evolved 14CO2 and soil components was studied under laboratory conditions. Total 14CO2 released accounted for 0.2 and 2.1 % of the applied 14C for abiotic and biotic assays, respectively. High recoveries of 14C under extraction of tetrahydrofuran and water from soil samples indicated that most of the rimsulfuron and its possible metabolites were available for leaching and degradation. Non extractable residues were mainly located in the 0–50 μm fraction and were formed in lower amounts in the abiotic assays.