Phosdrin (0,0-Dimethyl 1-carbomethoxy-1l-propen-2-yl phosphate) 
When labeled phosdrin was fed to cows, blood levels of phosdrin 
metabolites reached a peak between 2 and 4 hours after administration and 
the blood was essentially free of radiation within 24 hours. Within three 
days, //Z4 of the administered dose was excreted. Half this was excreted via 
the urine within 12 hours. All radioactivity in the feces was present as 
hydrolysis products. Dimethyl phosphoric acid was identified in urine from 
a cow treated with phosdrin and in human plasma incubated with phosdrin 
(246). 
In the presence of mouse liver enzymes and glutathion, cis-phosdrin 
was degraded to cis-desmethyl phosdrin and S-methylglutathione (1702). When 
the trans-isomer was tested, dimethylphosphate was obtained (1037). 
Information on the metabolism of phosdrin in plants is not complete. 
However, the limited information available indicated that this compound was 
decomposed in plants by an initial enzymatic hydrolysis of the carboxylic 
ester to form the corresponding free acid. This was quickly followed by 
cleavage of the vinyl phosphate bond and decarboxylation. The finding of 
desmethyl phosdrin acid in some studies indicated that there were at least 
two paths for degradation of phosdrin in plants (245, 1341). 
H CH 
CH.O Bd pace CH.0 ee 
pean ates ak anita as ROM ar ad 
Phosdrin Phosdrin Acid 
0 rome 0 Q © CH3 0 
(CH.0).-P-OH + Hostecnec” cH.o-p-0-t=CH-c7 
oie H 3 bp H 
= Desmethyl 
Phosdrin acid 
CH 
, 3 
HO-C=CH,, + CO. 
275 
