Hydrolysis of diazinon and diazoxon conform to a pseudo first-order 
rate in the pH range 3.1 to 10.9. Diazinon hydrolysis was rapid under 
acid conditions. At neutral or alkaline pH, the rate was lower. Diazoxon 
hydrolysis proceeded much more rapidly than diazinon. Using IR and UV with 
gas-liquid chromatography, 2-isopropyl-4-methy1l-6~hydroxypyrimidine was 
identified as the major hydrolysis product (1637). 
Diazinon 
pH ex 12 
3.14 706 minutes 
7.4 4435.8 hours i 
9.0 3263.0 hours ’ 
10.9 144.9 hours 
Sodium azide caused the disappearance of diazinon from distilled 
water by catalyzing its hydrolysis into diethylphosphorothioic acid, 
2-isopropyl-4-methy1l-6-hydroxypyrimidine and three other compounds not 
identified (1644). 
Microsomes, prepared from the livers of adult male rats, in the 
presence of NADPH), converted diazinon to diethyl phosphorothioate and 
phosphate and diazixin (1782). 
144 

