G.C, 4072 (2-Chloro-1-[2,4-dichlorophenyl]vinyl diethyl phospnate) 
Peak concentration of radioactive material in the urine of steers, 
after a spray application of p32-j abeled G.C,. 4072, occurred in samples 
collected at 3 hours post-treatment. Metabolism resulted in the elimi- 
nation of 9 or 10 radioactive compounds in the urine. Most of these 
have not been identified because pure standards are not available 
(Chamberlain and Hopkins, 1962). 
Guthion (0,0-Dimethyl S-[4-oxo-1,2,3-benzotriazin-3(4H) -ylmethyl1] 
phosphorodithioate) 
Using whole cockroach tissues and homogenates of these tissues, 
enzymes have been shown to be present that will activate guthion and 
degrade the active metabolite. By analogy to other studies, it is assum- 
ed that guthion is activated by oxidation to the corresponding phosphates. 
However, no metabolites have been identified (Murphy and DuBois, 1957; 
Nakatsugawa and Dahm, 1962). 
Using rat tissues, incubation of guthion with slices of brain, car- 
diac muscle, kidney, or skeletal muscle produced no active metabolite. 
When guthion was incubated with liver slices, an active anticholinesterase 
thought to be the oxygen analog was rapidly produced (DuBois and Murphy, 
1957). 
In the tissues and milk of cows fed guthion, four phosphorus~free 
metabolites, containing the benzazimide moiety, were found but not iden- 
tified (Everett et al., 1966). 
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