Thimet (Phorate) (0,0-Diethyl S-[ethylthio]methyl phosphorodithioate) 
Thimet-P32 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 0,0-diethyl phosphoric acid (172); 
0,0-diethyl phosphorothioic acid (80%); and 0,0-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 (15l). 
P32-1abeled thimet was orally administered to a lactating Holstein 
cow. Only hydrolysis products were present in the urine. Initially, 0,0- 
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 (151). 
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 
thimet persisted as such for as long as 32 days. By means of chromatography, 
infrared, and partitioning characteristics, four non-hydrolyzed metabolites 
were identified as the phosphorodithioate sulfoxide and sulfone, phoratoxon, 
phosphorothiolate sulfoxide and sulfone. 0,0-diethyl phosphorothioic and 
0,0-diethyl phosphoric acid were also found (150, 151, 357, 992, 1519, 1774). 
When labeled thimet was applied to soil, there was an initial loss 
by volatilization as great as 25% within one hour. After that, little or 
no volatilization occurred. A large portion of the remaining thimet was 
bound to the soil and could not be extracted with chloroform nor identified. 
As the amount of organic material present in the soil increased, the amount 
of thimet recovered decreased. Extraction, column chromatographic and 
partitioning techniques showed that soil applications of thimet were also 
partially oxidized and hydrolyzed (543). 
After exposure of the yeast-like plant Torulopsis to thimet, the 
presence of the phosphorodithioate, phosphorothiolate, and other products 
of oxidation and hydrolysis were shown (98). 
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