Persistence and fate of tebufenozide (RH‐5992) insecticide in terrestrial microcosms of a forest environment following spray application of two mimic® formulations
Abstract A terrestrial microcosm study was conducted to study the persistence and metabolic fate of tebufenozide in clay loam soil, forest litter, spruce needles and shoots after spray application of aqueous flowable (AF) and emulsion suspension (ES) formulation of tebufenozide, MIMIC®, at 35, 70 and 140 g active ingredient (A.l.)/ha. Soil, litter, spruce needles and shoots were collected at intervals of time up to 460 d post‐spray and analyzed by high‐performance liquid chromatography (HPLC) for the intact chemical. Droplet density, size spectra (DN.5 and Dv.5) and initial deposit data were gathered using collection units consisting of Kromekote® cards, glass fibre filters and glass plates. Droplet density, size spectra and deposition varied according to the formulation type sprayed. Deposit levels increased with dosage and the ES formulation usually gave higher deposition on the collectors compared to the AF formulation. Initial deposits (μg/g, fresh weight) were higher (ca. 150 %) on the spruce needles...