Comparative Degradation and Metabolism of Butonate, Trichlorphone and Dichlorvos

Reviews of Environmental Contamination and Toxicology

“…32P-Leptophos (181) on silica gel was photodegraded with formation of oxon, O-demethylated and debrominated derivatives, and O-methyl phenyl thiophosphonic acid that were finally degraded to phenyl phosphonic acid (Zayed et al 1978). Monocrotophos (156) (Dureja 1989;Lindquist and Bull 1967), phosphamidon (158) (Bull et al 1967), dichlorvos (153), and trichlorfon (179) (Derek et al 1979) do not have any chromophore to absorb sunlight and thus direct photolysis was most unlikely. These results show the insignificant differences in photochemistry among phosphorothioates, phosphoramidothioates, and phosphonothioates.…”

“…32 p _ and 14C-Dimethoate (165) was gradually degraded on leaves via P=S oxidation followed by conversion of the amide moiety finally to the carboxyl derivative of the oxon, including oxidative N-dea1kylation (Dauterman et al 1960;Lucier and Menzer 1968). Acephate (174), cyanofenphos (180), leptophos (181), and butonate (182), having P-C and P-N bonds in their molecules, underwent either O-dealkylation or ester hydrolysis, and photolysis on plant surfaces seemed to be of minor importance (Chiba et al 1976;Zayed et al 1978;Bull 1979: Derek et al 1979. Formothion (166) underwent rapid conversion to (165) on bean leaves but contribution of photolysis is unclear (Sauer 1972).…”