The metabolic fate ofN‐isopropyl‐N‐phenyloxamic acid in the rat and the milk goat

Rats excreted the 14C from a single oral dose of N‐isopropyl‐N‐[14C]phenyloxamic acid [I, a soil metabolite from 2‐chloro‐N‐isopropylacetanilide (propachlor)] in approximately equal quantities in the urine (49.2%) and feces (48.2%). A milking goat given daily oral doses of [ 14C]‐I (1 mg of I three times daily) excreted more 14C in the feces (53.6%) than it excreted in the urine. From both species, I accounted for 97 to 100% of the urinary 14C, and all of the 14C that was extractable from the feces (73 to 75% of the 14C in feces was extractable with methanol). Goat milk samples collected 16 hr after the last dose contained no detectable 14C. Tissue residues of 14C were determined.