Degradation of terbutryn in sediments and water under various redox conditions

Abstract
A laboratory study was conducted to examine the degradation of terbutryn [herbicide] in sediment and water under different redox conditions. Terbutryn degraded slowly in static aerobic systems (loosely capped flask, 25.degree. C) with half-lives (t1/2) of 240 and 180 days in pond and river sediment, respectively. Degradation products, identified by co-chromatography on TLC and HPLC [high performance liquid chromatography] systems, included hydroxy-terbutryn, terbutyrn-sulfoxide and N-deethyl terbutryn. Hydroxyterbutyrn was the major degradation product in sediments and water representing 60-70% of the extractable radioactivity after 515 days incubation. Under N aeration in respirometer flasks (redox potential -46 to +210 mV) degradation of terbutryn was slow with t1/2 > 650 days.