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a sex difference nor any marked difference in excretion profiles from the rats with no pre-treatment.
The excretion data for rats at 0.5 mg/kg bw showed that while enterohepatic recirculation was evident,
biliary metabolites were largely excreted in the faeces. At the lower dose, the half-life of excretion was
approximately 20 h. At 300 mg/kg bw, more of the administered dose w as excreted in the urine by noncannulated
rats than by bile-duct cannulated rats, apparently after reabsorption and further metabolism of
some biliary metabolites; however, the predominant route of excretion of biliary radioactivity was again
in faeces, as observed at the lower dose. At the higher dose, the half-life of excretion was approximately
33–48 h. At both doses, elimination kinetics were thus independent of sex and radiolabel position.
Tissue distribution
The concentration of radiolabel in the blood reached a maximum concentration (C max
) at 2 h
after oral administration in male rats at 0.5 mg/kg bw and declined rapidly thereafter. The AUC up
to 168 h after administration was 6.19 µg equivalent/h per ml. T max
was shorter in females than in
males and C max
and AUC in females reached only about 50% of the respective values in males. The
d isappearance of radioactivity in female rats was slightly faster than in male rats (Figure 2, Table 1).
Figure 2. Concentrations of difenoconazole equivalents in the blood of rats given a single oral
dose of radiobelled difenoconazole at (a) 0.5 mg/kg bw or (b) 300 mg/kg bw
(a) 0.5 mg/kg bw
(b) 300 mg/kg bw
From Esumi (1992)
DIFENOCONAZOLE 201–272 JMPR 2007