Decomposition of parathion in aqueous solution by ultrasonic irradiation

Parathion (O,O-diethyl O-p-nitrophenyl thiophosphate) is a major pesticide that is used in large quantities worldwide. Organophosphate esters such as parathion have been used as alternatives to DDT and other chlorinated hydrocarbon pesticides. However, the organophosphate esters are not rapidly degraded in natural waters. At 20 ºC and pH 7.4, parathion has a hydrolytic half-life of 108 days and its toxic metabolite, paraoxon, has a similar half-life of 144 days.