Mishnah Tevul Yom 3:6: If a pure person took a bite from some food, and it fell [along with his saliva] onto his clothes and onto a loaf of terumah, it is pure [i.e. the loaf has not been primed for impurity]. If one was eating split olives, or moist dates, as long as he wanted to suck on its pit, if it fell onto his clothes and onto a loaf of terumah, it is impure [i.e. the loaf has been primed to be susceptible to being rendered impure]. If one was eating dried olives, or dry dates, as long as it he did not want to suck on its pit, if it fell onto his clothes and onto a loaf of terumah, it is pure. Like these [cases, this rule applies] regarding both a pure person and a tevul yom. Rabbi Meir says: these and those [i.e. both cases] are impure with regard to a tevul yom, since liquids from an impure person prime [things to become susceptible to being rendered impure], whether in accordance with his desire or not in accordance with his desire. And the Sages say: a tevul yom is not considered an impure person [i.e. and therefore his liquids do not prime for impurity against his desire].

טהור שנגס מן האכל ונפל על בגדיו ועל ככר של תרומה, טהור. היה אוכל זיתים פצועים ותמרים רטבות, כל שהוא רוצה למץ את גרעינתו ונפל על בגדיו ועל ככר של תרומה, טמא. היה אוכל זיתים נגובין ותמרים יבשות, כל שאינו רוצה למץ את גרעינתו ונפל על בגדיו ועל ככר של תרומה, טהור. אחד טהור ואחד טבול יום, כאלו. רבי מאיר אומר, אלו ואלו טמאין בטבול יום, שמשקין של טמא מכשירין לרצונו ושלא לרצונו. וחכמים אומרים, אין טבול יום טמא:

Mishnah Tevul Yom 4:1: Regarding food taken as the [first] tithe, which was primed for impurity by a liquid, if it was then touched by a tevul yom [one who has immersed that day in a mikvah, but who must wait until nightfall to become fully pure, and is of a second degree impurity until then] or by one with soiled [i.e. impure] hands, terumat ma'aser [a tenth of the tithe given to a Levi which must, in turn , be given to a kohen and which becomes holy upon separation, and can only be consumed by kohanim or their household] may be separated from it in purity, because it is of a third degree [level of impurity], and something of a third degree is pure with regard to chullin [produce or food that is not sanctified, and is permitted for general consumption].

אֹכֶל מַעֲשֵׂר שֶׁהֻכְשַׁר בְּמַשְׁקֶה, וְנָגַע בּוֹ טְבוּל יוֹם אוֹ יָדַיִם מְסֹאָבוֹת, מַפְרִישִׁין מִמֶּנּוּ תְרוּמַת מַעֲשֵׂר בְּטָהֳרָה, מִפְּנֵי שֶׁהוּא שְׁלִישִׁי, וְהַשְּׁלִישִׁי טָהוֹר לְחֻלִּין: