Fluvalinate metabolism by rats

Within 4 days of receiving a single oral dose of (trifluoromethyl- super(14)C)fluvalinate at 1 mg/kg by gavage in corn oil, rats excreted 9-19 and 75-88% of the applied dose in urine and feces, respectively. About 45% of the applied radiolabel was excreted in feces as unmetabolized fluvalinate, while the major fecal metabolite (11% applied dose) was an anilino acid that arose from hydrolysis of the parent ester. This anilino acid formed fecal conjugates with amino acids (glycine, serine, threonine, valine), bile acids (cholic, taurocholic, taurochenodeoxycholic), and glycerol (also oleoyl- and linoleoylglycerol). The amide of 2 was also present (3% of fecal super(14)C). The conjugations of an acidic xenobiotic with threonine, glycerol, and monoglycerides, as well as conversion to an amide, are to our knowledge novel conversions. The major metabolites in urine were hydroxymethyl-2 and 2-amino-3-chloro-5-(trifluoromethyl)phenol (as a sulfate conjugate), representing up to 46 and 24% of the urinary super(14)C, respectively. Pharmacokinetic behavior (blood and bile) and numerous metabolic variables were investigated.