If the concentration is below a certain level, these enzymes are sufficient to counteract the Rotenone that is present. Because fish absorb Rotenone rapidly through their gills, they more quickly absorb a lethal dose. By adding potassium permanganate or chlorine to the water at levels equal to the Rotenone. The speed with which Rotenone breaks down varies with temperature, light, oxygen content and alkalinity of the treated water. In general, most treated waters are detoxified after 5 weeks.
Rotenone is only very slightly mobile in soil.
In most soils, Rotenone is unlikely to move as much as one inch. Even in sandy soil, Rotenone binds strongly to organic matter in the soil, which further prevents it from reaching groundwater. In addition, the fact that Rotenone degrades rapidly, its residues would not persist in groundwater. However, as a precaution, swimmers should consider waiting at least 24 hours before entering a treated pond or lake. The simplest is to place live fish in a cage and immerse them in the water for several days.