It seems to be allowed without fear.
Sources:
The main reason for this permission is, as explained in the previous answers, that in any way that it is evident that the blood is human blood, there is no prohibition in it. Paz.
And likewise, it must be discussed to add two more sides to this, the first that this blood is mixed with toothpaste and the second that he puts something in his mouth that is less than a lesson without swallowing, and this is not simply for the prohibition Afi' in Isorin, and A. in 16 in Yod C. C "8 What discusses whether it is to be compared to the Lord Ta'anit.
And to the body of the matter discussed about tasting with prohibition, the meaning of the 16th opinion there in Rish C. Tzach is that it should not be made easy if it is put into the mouth, and it should be noted that the same is said in the Shach B. C. Kah Skachad in the name of the Rabbis C. Rafah tasting with prohibition It was not allowed at all and since it is also explained in the words of the Rama in the name of Sai'5, and what is the gist of the permission that I wrote is for the reason that it is evident that it belongs to a person whose permission is sufficient as explained in its place, and other additions are only to remove the fear from the mind of Rashi who forbids blood in a way that is obvious as explained in its place, However, Shashi Rashi did not rule on the halacha.
And really, if the prohibition is mixed with toothpaste, it is easier for the sake of taste, and Yaoi' in the opening of the answer to Rish C. Cet.
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