When fenpyroximate is administered orally to rats,
radiocarbons from 14C-fenpyroximate are rapidly and
almost completely excreted in the urine and feces
within 72 h, and fenyproximate seems to be
metabolized via oxidation of the tert-butyl group and
methyl group at the 3-position in the pyrazole ring, p-
hydroxylation in the phenoxy moiety, N-demethylation,
hydrolysis of the tert-butyl ester, cleavage of the oxime ether bond, and/or E/Z isomerization. In soils, 12
degradation products are identified, and in sterilized
soils the degradation of fenpyroximate and CO2,
evolution are negligible. Fenpyroximate degrades
through hydrolysis of tert-butyl ester, isomerization or
cleavage of the oxime ether, N-demethylation,
oxidation of the methyl group at the 3-position on the
pyrazole ring, and hydroxylation of the phenoxy ring,
and is finally mineralized to CO2 and/or bound to soil
organic matter.