High Performance Liquid Chromatographic Determination of an Asymmetrical Triazine Herbicide from Soil

A rapid method for determining residues of the herbicide metribuzin in soil by laboratory experiment under controlled conditions is described. Field soil fortified with herbicide at concentration of 5 mg kg-1 soil, and maintained at field capacity moisture regime and kept at ambient temperature 25 ± 5°C. The soil samples were extracted with different ratio of methanol/water solution and the residue was estimated by HPLC with UV detection at 290 nm and a flow rate of 0.5 ml/ min. The detection limits were 0.05 mg/kg in soil. The results indicate 52.55% degradation of metribuzin in soil samples on 120-days of experiment. The methanol/water (4:1 v/v) was found to be most effective in metribuzin degradation recovery and enhances the recovery as compared to the other. The proposed method has been satisfactorily applied in soil samples showing recoveries ranging from 85% to 98% and represents a valuable procedure for analysis of metribuzin by high performance liquid chromatography (HPLC).