Reference for Pesachim 35:5

רב אשי אמר לעולם בטלו במעיה לגמרי משום דהוה ליה משקה סרוח

In respect of light uncleanness, but not in respect of grave uncleanness, for R'Judah maintained: It is nullified in its bowels. R'Ashi said: In truth it is completely nullified in its bowels, beca it is [now] noisome liquid.<span class="x" onmousemove="('comment',' And undrinkable, whereas only drinkable water defiles. hxuh 'r');">⁵</span>

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