Degradation of active biocide compounds in five commercially available pesticides ranged from 0–75% after a 24 hr irradiation period in the presence of anatase (TiO 2). Nearly identical results, with the exception of triadimefon, were obtained from simulated rinsates with and without admixed soil. This study provides a realistic assessment of the photocatalytic treatment of rinsates in a slurry reactor by utilizing a mixture of commercial products, high concentrations, admixed soil, and solar equivalent UVA lighting.