Reference for Chullin 67:16

ורבי יהושע

But argue thus: We find that the unclean food is more unclean than the eater thereof, for foodstuffs [can become unclean] from an egg's bulk [of unclean food], whereas the eater [of unclean food does not become unclean] unless he has eaten the size of two eggs thereof.<span class="x" onmousemove="('comment',' Lit., 'the quantity of half of half a loaf', equivalent to the size of two eggs. V. 'Er. 82b.');">⁷</span>

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