Interaction of formulation and soil components on the aqueous concentration of fluridone

Fluridone was added as an aqueous suspension (AS), 5% slow-release pellet (SRP), or a 5% pellet (5P) to deionized water which contained settled sand, kaolin, bentonite, or peat. Fluridone formulated as AS was detected in water immediately after application. Fluridone release from 5P pellets was faster than SRP pellets regardless of the time at which pellet integrity was lost. A period of 72 or 400 hours was required for total release of fluridone from the two pellet formulations when agitated vigorously or mildly, respectively. Fluridone adsorption to bentonite was non-linear (S-type), while adsorption to kaolin and peat was linear (Langmuir or L-type). Quartz sand adsorbed little (