Tohoros 4:2-3

Tohoros 4:2

Let’s say that a weasel had a dead vermin in its mouth and it walked over some loaves of trumah. If we don’t know whether or not the vermin touched them, the loaves in doubt remain clean.

Tohoros 4:3

If a weasel had a (dead) vermin in its mouth or a dog had carrion in its mouth and it passed between ritually-clean people, or if ritually-clean people passed between them, the doubtful situation is ruled clean since the impurity had no resting place. If the animal was picking at the impurity on the ground and a person said that he went to that place but he doesn’t know whether or not he touched it, the doubtful situation is ruled unclean since the impurity had a resting place.