Quantification methods of folpet degradation products in plasma with HPLC-UV/DAD: Application to an in vivo toxicokinetic study in rats

Solid-phase extractions followed by HPLC-UV/DAD methods were developed for occupational biological monitoring or forensic investigations of the fungicide folpet using its degradation products, phthalimide and phthalamic acid as plasma biomarkers. These methods show good linearity (r > 0.9955), precision (CV < 15%) and accuracy (bias < 14.8%). The lower limits of quantification for phthalimide and phthalamic acid were 10 and 20 ng/ml and the absolute recoveries were higher than 86% and 68%, respectively. Applying these methods, a plasma toxicokinetic study of folpet in rats after intratracheal administration of Folpan 80WG® showed that inhalation of folpet could be a route of exposure with an important systemic absorption.