Azinphosmethyl (Guthion) [0,0-Dimethyl S-[4-oxo-1,2,3-benzotriazin—3- (4H) - 
ylmethyl] 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 assumed that 
guthion is activated by oxidation to the corresponding phosphates. However, 
no metabolites have been identified (1060, 1067). 
Using rat tissues, incubation of guthion with slices of brain, cardiac 
muscle, kidney, or skeletal muscal produced no active metabolite. When 
guthion was incubated with liver slices, an active anticholinesterase thought 
to be the oxygen analog was rapidly produced (385). 
In the tissues and milk of cows fed guthion, four phosphorus-free 
metabolites, containing the benzazimide moiety, were found but not identified 
(421). 
Activation and degradation of azinphosmethyl by liver microsomes of 
chicken, muscovey ducks, albino rats, mice guinea pigs, sheep, cattle and 
hogs was studied. Percent activation of azinphosmethyl (See table I) was 
calculated from the following formula: 
I_,. directly assay P(0O) analogue 
50 
pLegt ee ee he el ee, OG 
Teo incubated insecticide 
44 

