Why Should Fingernails Be Flushed Down the Toilet?

Hello,

1. It is written in Tractate Niddah (17a) that if a pregnant woman steps on fingernails she may miscarry. Therefore, it is said there that one who burns his fingernails is a pious person, since there is no possibility that these fingernails will harm a pregnant woman; one who buries them is a righteous person, because it is still possible that they may be found again, and therefore he is not in the category of a pious person, see Rashi there. And one who throws them away is wicked.

Based on the above, there is a measure of piety in burning the fingernails, although one may initially throw them into the toilet, and this is preferable to burying them (see what is brought about this in Piskei Teshuvot, siman 260, letter 9).

2. If the fingernails fell accidentally and you cannot find them, the room should be swept, because once the fingernails have moved from their place, they no longer have the power to cause harm (see Birkhei Yosef, siman 260, letter 6, and Mishnah Berurah there, seif katan 6).

Blessings,

Hillel Meirs