Before POIS, sometimes when I masturbated, I would spread the result all over my abdomen, for lack of something present to clean it up. It would sort of absorb like a cream.
That never produced any bad results at all. That would be akin to someone without POIS doing the test you mention.
I haven't tried this now that I have POIS. I don't masturbate, I prefer to save if for wifey!
There is always some residue however, so I guess I could try spreading that on my hand or arm.
I'm sure that clean-ups must get some on my hands (although not much) but without any results.
I'll give it a try though "with whatever is left".