Determination of metribuzin and major conversion products in soils by microwave-assisted water extraction followed by liquid chromatographic analysis of extracts.
A multiresidue method developed for the analysis of metribuzin and its major conversion products, deaminometribuzin (DA), diketometribuzin (DK) and deaminodiketometribuzin (DADK), in soils is presented. The method is based on microwave-assisted water extraction (MAWE) of soils using 10 mM phosphate buffer, pH 7 as extractant and analysis of aqueous extracts by HPLC-diode array detection. MAWE operational parameters were optimized with respect to extraction efficiency of the target compounds from soils with 1.5 and 3.5% organic matter content. Recoveries of all solutes above 80% were obtained from soils with 1.5% organic matter content; respective LOD and LOQ levels were determined at 5 and 10 micrograms/kg. In soils with organic matter content 3.5%, recoveries of all solutes were lower (< 70%) and the respective LOD and LOQ values were determined at 10 and 50 micrograms/kg. However, recoveries of fresh and aged residues, the latter weathered under cold storage conditions, were not statistically different for both types of soils.
Papadakis
Emmanuil N
EN
Pesticide Science Laboratory, Aristotle University, P.O. Box 1678, 54006 Thessaloniki, Greece.
Papadopoulou-Mourkidou
Euphemia
E
D002851:Chromatography, High Pressure Liquid / Q000379:methods*; D006540:Herbicides / Q000032:analysis*; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity; D012989:Soil Pollutants / Q000032:analysis*; D014227:Triazines / Q000032:analysis*
D006540:Herbicides; D012989:Soil Pollutants; D014227:Triazines; C009235:metribuzin