Chlorfenvinphos (Supona, SD 7859, GC-4072, Birlane) [2-Chloro-1-(2,4- 
dichlorophenyl) vinyl diethyl phosphate] 
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Peak concentration of radioactive material in the urine of steers, 
after a spray application of P?4-labeled chlorfenvinphos, occurred in 
samples collected at three hours post-treatment. Metabolism resulted in 
the elimination of 9 or 10 unidentified radioactive compounds in the 
urine (266). 
Residues of chlorfenvinphos and trichloroacetophenone were below 
limits of detection in organs of exposed sheep. Residue levels never 
reached 0.1 ppm (1224). 
After oral administration to rats and dogs, C!*-chlorfenvinphos 
was rapidly metabolized and excreted. About 90% was eliminated in the 
urine; the remainder, via feces and, to a lesser extent, via expired 
gases. In rats, 32.3% of the dose was accounted for by 2-chloro-1l- | 
(2,4-dichlorophenyl) vinyl monoethyl phosphate (II); 41%, by 1-(2',4'- 
dichlorophenyl) ethyl 8-D-glucopyranosiduronic acid (VI); 72%, by 2,4- 
dichloromandelic acid (XI); 2.6%, by 2,4-dichlorophenylethanediol 
glucuronide (X); and 4.3%, by 2,4-dichlorohippuric acid (IX). In dogs 
this was 69.6% (II); 3.6% (VI); 13.4% (VII), 2.7% (X) (704). 
After intravenous administration, chlorfenvinphos was rapidly 
metabolized to the O-desethyl analog (II) (83%), compound XI (9%), 
and compound VI (8%) (704) in dogs. 
Metabolism of the intermediate metabolites was also studied. After 
oral administration of compound II to a dog, XI (40%), VI (50%) and un- 
changed II (10%) were found in the urine. Following oral administration 
of labeled 2-chloro-1-(2,4~-dichlorophenyl) ethanol, 80% of the label 
appeared as the corresponding glucuronide and 20% as compound XI. Since 
the glucuronide did not occur among the metabolic products of 
chlorfenvinphos, it is unlikely that the ethanol compound is a metabolite 
of the insecticide, at least in dogs (704). 
Orally administered 2,4-dichlorophenacyl chloride (III) was excreted 
almost quantitatively by rats via the kidneys in urine as XI (30%), IX 
(5%), and VI (60%) (704). 
Recent studies have shown that this compound reacted with and 
was bound by proteins in the blood plasma of mammals and in homogenates 
of house fly heads (155). 
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