Don't confuse good science with bad.Dirty fish CAN be made clean, but I don't know how long it takes.
Dirty and poisons are not the same thing.
You can not "flush" PCB's and Mercury from the flesh of fish. Tanking fish in clean water is a waste of time. That is more about live crawfish.
The biggest risk of water in the White is getting it on you or in open wounds.........bacteria. I never let my dog swim in the white river except in winter. After big rains the overfow sewers along Fall Creek flush tons of turds into the creek and that flows into the white. Drive Fall Creek on a hot humid day south of the State Fair grounds. Take a good wiff when you do.