Reference for Chullin 70:11

טומאה בחבורין שאני דמגו דמהימן אקדש מהימן נמי אתרומה

R'Huna B'Nathan raised this objection: [We have learnt:] Common food which is unclean in the second degree renders [by contact] common liquids unclean [in the first degree], and renders those who eat terumah unfit.

Jastrow