DETERMINATION OF FENOXAPROP-ETHYL IN POLISHED RICE AND BROWN RICE BY HPLC

A rapid and sensitive method for the determination of fenoxaprop-ethyl in polished rice and brown rice by HPLC was developed. The pesticide was extracted from samples with acetonitrile. For polished rice, the e xtract was evaporated to dryness. For brown rice, the fats in the extr act were removed with hexane saturated with acetonitrile, and the acet onitrile layer was evaporated to dryness. The residues were dissolved in hexane, and the hexane solution was cleaned-up with a Sep-pak(R)Flo risil column. Recoveries of fenoxaprop-ethyl were 87.2-104.6% for poli shed rice and 88.3-108.3% for brown rice. No pesticide was found in 6 polished rice and 41 brown rice samples from the U.S.A.. The detection limits of fenoxaprop-ethyl in polished rice and brown rice were both 0.01 ppm.