Study on the sensitized photolysis of pyrethroids; 1. Kinetic characteristic of photooxidation by singlet oxygen

The kinetic characteristic of photolysis of cypermethrin sensitized by methylene blue, riboflavin and rose bengal is studied. The relationship between 1/Kexpt1 and [A] confirms the mechanism of singlet oxygen photooxidation. Values of CPM in the presencce of methylene blue and riboflavin are 6. 49 × 10−6 and 2. 27 × 10−6mol−1 • L • s−1 respectively. The effective factors such as concentration of sensitizer, atmosphere, probe for ʹOz and polarity of solvents are discussed for the photooxidation kinetics of CPM.