So I recently cast Necrotic Radiation on an area
You imbue the touched object or space with slow-acting necrotic radiation. "Range touch; Target one object or one 10-footsquare area
Duration 24 hours
If you cast the spell on an object, any creature ending its turn holding or carrying the object takes 2d6 negative damage. If you cast the spell on an area, any creature ending its turn in the area takes 2d6 negative damage. You can attempt to use this spell on an attended object by touching the object. If you do, the creature attempts a Reflex save to reduce the effect."
In all of the results it reads only for the casting on an item. So does the area attack really last for 24 hours?