Reference for Numbers 19:22

וְכֹ֛ל אֲשֶׁר־יִגַּע־בּ֥וֹ הַטָּמֵ֖א יִטְמָ֑א וְהַנֶּ֥פֶשׁ הַנֹּגַ֖עַת תִּטְמָ֥א עַד־הָעָֽרֶב׃ (פ)

And whatsoever the unclean person toucheth shall be unclean; and the soul that toucheth him shall be unclean until even.