Metabolism of phenothrin or 3-phenoxybenzyl d-trans-chrysanthemumate in mammals

Carbon-14 d-trans-phenothrin or 3-phenoxybenzyl d-trans-chrysanthemumate labeled at the hydroxymethyl group in the alcoholic moiety was administered orally to male Sprague-Dawley rats at the rate of 200 mg/kg. The compound was rapidly absorbed from the gastrointestinal tract and distributed into various tissues.Radioactivity was rapidly eliminated (over 3 days) via the urine (ca. 60%) and feces (ca. 40%). No detectable radioactive carbon dioxide was expired. The urinary and fecal metabolites were separated and identified, the predominant one being 3-(4′-hydroxy) phenoxybenzoic acid and amounting to approximately 55% of the recovered radioactivity. 3-Phenoxybenzoic acid, free and conjugated with glycine, was also identified. In vitro studies using liver preparation from rats, mice, guinea pigs, rabbits, and dogs revealed that d-trans-phenothrin was hydrolyzed to 3-phenoxybenzyl alcohol, which was subsequently oxidized. The l-trans isomer was also easily hydrolzyed, whereas d-cis- and l-cis-phenothrin were resistant to hydrolytic attack at the ester linkage.