Kinetics of chemical degradation of malathion in water

Potential chemical and photochemical pathways for the degradation of malathion were investigated in laboratory kinetic studies. The results of acid-catalysed degradation and of oxidation indicate that these pathways would be too slow to be of significance in the aquatic environment, but photolysis could be important under acid conditions. Malathion was much more susceptible to alkaline degradation, and underwent two competing reactions at 27C . The persistence of the malathion monoacids formed was also studied, and they proved to be 18 times more stable than malathion under the same conditions. (JOK)