Dissipation studies of fentrazamide (YRC-2388) in soil under anaerobic condition

Abstract

Dissipation of fentrazamide in soil and water under flooded (anaerobic) conditions was studied. Fentrazamide was applied to soil at 100 g ha⁻¹. Soil was extracted with 0.1 N HCl : acetone (1 : 1 v/v) followed by partition and cleanup with silica SPE. Separation was achieved in an ODS-II column with a mobile phase of acetonitrile : water (70 : 30 v/v) and detection at 214 nm. Recovery of fentrazamide varied from 75.2–90.4% and 89.9–97.8% in soil and water, respectively. Fentrazamide dissipated rapidly and fentrazamide residues were not detected after 100 and 35 days of application in soil and water, respectively. Half life in soil and water was 9.06 and 3.66 days, respectively. Dissipation followed monophasic first order kinetics pattern. No fentrazamide was detected in soil, rice grain and rice straw at harvest of crop. Calibration curves for quantification were linear and relative standard deviation (RSD) was 1.78%. LOD for instrument was 0.002 μg mL⁻¹ and LOQ for methods were 0.005 μg g⁻¹ for soil and water.