Propanil and TCAB Residues in Rice Soils

This is the authors' abstract. We don't add key points for this paper.

We surveyed soils that produce rice(Oryza SativaL.) at the University of Arkansas Rice Branch Experiment Station at Stuttgart, Arkansas, to determine whether residues of 3, 3′,4,4′-tetrachloroazobenzene (hereinafter referred to as TCAB) accumulated with repeated applications of 3′,4′-dichloropropionanilide (propanil). We sampled Crowley silt loam with known histories of propanil application to determine the effect of depth, rate, and time on TCAB formation. Propanil and TCAB were measured by electron capture gas chromatography. Low concentrations of TCAB (<0.2 ppm) generally were detected in the surface 0 to 10.1-cm layer of soil receiving applications of propanil at rates of 6.7 kg/ha. Concentration and occurrence of TCAB decreased with increasing time and depth in soil.