| Abstract
| - Acifluorfen (AC),5-[2-chloro-4-(trifluoromethyl)phenoxy]-2-nitrobenzoic acid, wasapplied to anorganic soil at 220 mg kg-1 in a laboratoryincubation study. A conventional extraction methodwith solvents and supercritical fluid extraction (SFE) were used toevaluate extractable andnonextractable (bound) residues of AC and its metabolites in the soil.Over an incubation period of7 months, the soil contained 22% AC of the initially applied herbicideand the residues were almostcompletely extracted with aqueous methanol. Only 0.8% AC wasfound in the bound form. Seventy-five percent AC applied was degraded to aminoacifluorfen (AAC) (due toreduction of nitro group toamino group) of which 60% was extracted by aqueous methanol, and 15%was in the bound form,mainly associated with the humin fraction of the soil organic matter.No further transformation ofAAC to other metabolites was observed. Keywords: Acifluorfen; bound residues; soil; SFE
|
