Method for Bioassaying Chlorsulfuron in Soil and Water

Abstract

Bioassay techniques were evaluated for the determination of chlorsulfuron {2-chloro-N-[[(4-methoxy-6-methyl-1,3,5-triazin-2-yl)amino] carbonyl] benzenesulfonamide} residues in soil and water. A linear response of corn (Zea maysL.) primary root length to chlorsulfuron concentrations (InX+1) of 0.0 to 16.0 μg/L was observed in the water bioassay. Several soil extraction bioassay methods were attempted and found to be highly variable. A Ca(OH)2soil extraction bioassay technique produced a linear response of primary corn root length to chlorsulfuron concentrations ranging from 0.0 to 64.0 μg/kg. The efficiency of the Ca(OH)2extraction bioassay was determined by the use of14C-chlorsulfuron. Recovery efficiency at 1.0 μg/kg was 74% and averaged 62% at all higher chlorsulfuron concentrations.