Disposition of fipronil in rats

In the scientific literature, little attention has been paid to the disposition of fipronil, a phenyl pyrazole insecticide. In this study, the tissue distribution, the metabolic fate, and the elimination of fipronil was investigated in rats using radiolabeled fipronil. When a single oral dose of ¹⁴C-fipronil (10 mg kg⁻¹ b.w.) was given to rats, the proportion of dose eliminated in urine and feces 72 h after dosing was ca 4% for each route. At the end of the experiment the highest levels of radioactivity were found in adipose tissue and adrenals.