Thank you for your two enlightening answers, and for your precious time which you spent to do the research and response.

One last question on the same subject: By nega tohor, what tuma are we trying to remove from the person who is bringing a korban ? Earlier on bottom of 132a, Rashi writes that the tuma can apply to the owner of the korban , or to the cohen who does the avoda. I was thinking that for the cohen, he wants to remove a nega tohor because it is a chatsitsa on his hand during avoda , or between his foot and the floor or between his flesh and his clothing. However, this doesn't apply to the owner of the korban whose concern is only tumo. But by nega tohor the gemara just said that he has no problem with erev shemesh. Does he have another tumo problem which goes away before erev shemesh as soon as he removes the nega tohor? If yes, what tuma is that ? And if no, then is the issue of nega tohor only appl icable to the cohen due to chatsitsa and to a bris mila ?

Thank you.

Nosson Munk