| Abstract: | The excretion patterns and tissue residues were determined after single and repeated oral dosing of rats with triazophos-14C Within 4 days after a single oral dose 76.3 % of the 14C was excreted in the urine and 21.0% in the faeces. After daily application for 12 days 69.5–83.4% of the label was eliminated in urine and 30.9–18.1 % in the faeces. Following prolonged application, however, elimination is distinctly slower. Distribution of radioactive residues in organs and tissue in both test series showed no appreciable or critical concentrations of radioactivity, with the exception of the gastrointestinal tract (contents and walls). Unchanged triazophos and l-phenyl-1,2,4-triazol-3-ol-3-14C were excreted in the faeces. Renewed release of other metabolites into the gastrointestinal tract apparently does not take place. The following metabolites are detected in the urine: urea-14C (approx. 85% of the radioactivity excreted with the urine); and three compounds as conjugates with glucuronic acid, i.e. 1-phenyl-l,2,4-triazol-3-ol-3-14C (approx. 3%), l-phenylsemicarbazide-3-14C (approx. 5%), and semicarbazide-14C (approx. 5%). Two further metabolites, so far unidentified, occurred in small quantities. |
