U.S. Geological Survey Toxic Substances Hydrology Program--Proceedings of the Technical Meeting, Colorado Springs, Colorado, September 20-24, 1993, Water-Resources Investigations Report 94-4015

The Transport and Degradation of Cyanazine Metabolites in Surface Water of the Midwestern United States

Abstract

Cyanazine was detected in 73 percent, cyanazine amide in 65 percent, deethylcyanazine in 36 percent, and deisopropylatrazine in 52 percent of the samples collected during the first storm runoff after herbicide application in a reconnaissance study of stream water from 122 basins in a 10-State area in the Midwestern United States in 1989. Furthermore, these compounds were detected in as many as 30 percent of the samples collected in the spring before planting and in the fall of the year during low streamflow. Analysis of samples collected from several stream sites during storm-runoff throughout the spring and early summer of 1990 indicate that cyanazine degrades to deisopropylatrazine and that the deisopropylatrazine-to-deethylatrazine ratio (D²R) is an indicator of the amount of cyanazine relative to atrazine that is used in the basin.