All perfect praise be to Allaah, The Lord of the Worlds. I testify that there is none worthy of worship except Allaah, and that Muhammad, sallallaahu ‘alayhi wa sallam, is His slave and Messenger.
What we have mentioned is not our own words; rather, they are the words of earlier scholars. They mentioned dead skin as an example of the obstructions that must be removed for purification would be valid.
Addressing such obstructions, the Maaliki book of Fiqh, Bulghat as-Saalik, reads: “Like the filth that is accumulated on the body, among which is the dead skin.”
Also, the Shaafi‘i book Haashiyat al-Jamal reads: "... and one must remove wax that prevents water from reaching the skin, but there is no harm in the color traces of paint or grease; and one must remove dead skin and the dirt that is under the fingernail that prevents water (from reaching the skin).” [End of quote]