Photolysis of herbicide safener Mefenpyrdiethyl under sunlight irradiation: An analytical and GC/MS investigation

Photolysis of the herbicide safener mefenpyer-diethyl by sunlight irradiation in aqueous buffer solution (ph 6.9) was investigated bygaz chromatography /mass spectra (gc/ms).notable photodegradation of mefenpyrdiethyl was observed at investigated ph. photodegradation rate followed first-order kinetics with significant correlation coefficient. the t1/2 value was 1.20h. four metabolites were detected and identified according to gc-ms spectral data. photoproducts pp1 and pp2 show their maximum intensities after 3 h of irradiation after which they also began to degrade into metabolites pp3 and pp4. to our knowledge,the photoproducts pp2 and pp4 were detected previously in mefenpyrdiethyl hydrolysis process.