Thimet (Phorate) (0,0-Diethyl S-[ethylthio]methyl phosphorodithioate) 
Thimet-P22 in oil was administered orally to male albino rats. Ex- 
cretion in feces and urine varied with applied dosage. Hydrolysis products 
appearing in urine of the rats within 2 days were separated by ion exchange 
chromatography and found to consist of 0,O-diethyl phosphoric acid (17%); 
0,0-diethyl phosphorothioic acid (80%); and 0,O0-diethyl phosphorodithioic 
acid (3%). Using rat liver slice preparations, phosphorodithioate 
sulfoxides and sulfones and phosphorothiolate sulfoxides and sulfones 
were formed; and less than 1% of the radioactive metabolites appeared as 
hydrolysis products or unextractable residue from the proteins (Bowman 
and Casida, 1958). 
p32-jabeled thimet was orally administered to a lactating Holstein 
cow. Only hydrolysis products were present in the urine. Initially, 
0,O-diethyl phosphorothioic acid was excreted. This declined as 0,0- 
diethyl phosphoric acid increased. Some 0,0-diethyl phosphorodithioic 
acid was also excreted. Similar findings were obtained with bile fluid. 
Fractionation and partitioning showed that the initial oxidation products 
in feces were the sulfoxide and/or sulfone. The highest total tissue 
residues appeared in liver, kidney, lung, alimentary canal, and glandular 
tissues, Fat samples were very low in thimet metabolites (Bowman and 
Casida, 1958). 
After thimet was applied to plants, total anticholinesterase activity 
increased for several days and there was an increase in the amount of 
material that is more polar in its solubility properties. However, some 
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