Mishnah Taharos 1:9: Sanctified loaves whose ridges have sanctified [i.e. sufficiently pure] water in them, if one of them became impure by [coming into contact with] a vermin, they all become impure [any loaves touching it, along with any loaves touching those loaves, and so on, since even a fourth degree impurity, which generally does not generate further impurity, can render sanctified liquids primary, meaning they can then go on to render the rest of the loaves impure]. With [loaves of] terumah, [a vermin that comes into contact with one of them] makes two [loaves] impure and invalidates one [i.e the first loaf that touched the vermin becomes impure in the first degree, and any loaf that touches that loaf becomes impure in the second degree, and any loaf touching that loaf becomes impure in the third degree and thus is still invalid for terumah, but it does not cause any more impurity]. If there is dripping liquid between them, even with [loaves of] terumah, everything is impure [because the liquid, which is made primary by the loaves, and which causes the loaves it then touches to become secondary, and those loaves, in turn, cause the water touching the next loaves to become primary, and so on, to all the loaves].

כִּכְּרוֹת הַקֹּדֶשׁ שֶׁבְּתוֹךְ גֻּמּוֹתֵיהֶם מַיִם מְקֻדָּשִׁים, נִטְמֵאת אַחַת מֵהֶן בְּשֶׁרֶץ, כֻּלָּן טְמֵאוֹת. בַּתְּרוּמָה, מְטַמֵּא שְׁנַיִם וּפוֹסֵל אֶחָד. אִם יֵשׁ בֵּינֵיהֶם מַשְׁקֶה טוֹפֵחַ, אַף בַּתְּרוּמָה, הַכֹּל טָמֵא:

Mishnah Taharos 2:1: A woman who was pickling vegetables in a pot and touched [with impure hands] a dry part of a leaf outside the pot [but which was partially immersed, or connected to a stalk immersed in the pot], even if it [the entire leaf] has the equivalent of an egg [in volume], it is impure, and everything else is pure [because when her impure hands, which are a second degree impurity, touched the dry part of the leaf, it became a third degree impurity, which does not generate further impurity]. If she touched a wet part, if it has [at least] the equivalent of an egg [in volume], everything is impure; if it does not have the equivalent of an egg, it is impure and everything [else] is pure. If it [the wet part of the leaf] returns to the pot, everything is impure. If it [her hand] had been rendered impure through contact with a dead body, and she touched either a moist or dry part [of a leaf sticking out of the pot], if it has the equivalent of an egg [in volume], everything is impure; if it does not have the equivalent of an egg, it is impure and everything [else] is pure. If a woman who had immersed that day [and therefore was still of a second degree impurity until sunset] was emptying the pot with dirty [i.e. impure] hands and she saw liquids on her hands, and it is doubtful as to whether they were splashed from the pot, or that the stalk touched her hands, the vegetable [connected to the stalk] is invalid [i.e. impure], and [the rest of] the pot is pure.

הָאִשָּׁה שֶׁהָיְתָה כוֹבֶשֶׁת יָרָק בִּקְדֵרָה וְנָגְעָה בְעָלֶה חוּץ לַקְּדֵרָה בְמָקוֹם הַנָּגוּב, אַף עַל פִּי שֶׁיֶּשׁ בּוֹ כַבֵּיצָה, הוּא טָמֵא וְהַכֹּל טָהוֹר. נָגְעָה בִמְקוֹם הַמַּשְׁקֶה, אִם יֶשׁ בּוֹ כַבֵּיצָה, הַכֹּל טָמֵא. אֵין בּוֹ כַבֵּיצָה, הוּא טָמֵא וְהַכֹּל טָהוֹר. חָזַר לַקְּדֵרָה, הַכֹּל טָמֵא. הָיְתָה מַגַּע טְמֵא מֵת וְנָגְעָה, בֵּין בִּמְקוֹם הַמַּשְׁקֶה בֵּין בְּמָקוֹם הַנָּגוּב, אִם יֶשׁ בּוֹ כַבֵּיצָה, הַכֹּל טָמֵא. אֵין בּוֹ כַבֵּיצָה, הוּא טָמֵא וְהַכֹּל טָהוֹר. הָיְתָה טְבוּלַת יוֹם מְנַעֶרֶת אֶת הַקְּדֵרָה בְּיָדַיִם מְסֹאָבוֹת, וְרָאֲתָה מַשְׁקִין עַל יָדֶיהָ, סָפֵק מִן הַקְּדֵרָה נִתְּזוּ, סָפֵק שֶׁהַקֶּלַח נָגַע בְּיָדֶיהָ, הַיָּרָק פָּסוּל וְהַקְּדֵרָה טְהוֹרָה: