The following do not convey tumah nor do they effect hechsher: sweat, pus, and excrement, and the blood that emerges with them, and the fluids of a child [born] in the eighth month. R’ Yose says: Except for his blood. And someone who drinks the water of Tiberias, even though [the excretion] that emerges is clear. Blood of slaughter of a domesticated animal, of a non-domesticated animal, and of fowl that are non-kosher; and blood of bloodletting for therapeutic purposes. R’ Elazar considers these to be tamei. R’ Shimon ben Elazar says: Milk of a male is tahor.

The milk of a woman will cause [susceptibility to] tumah [whether its emergence is] to [one’s] satisfaction or is not to [one’s] satisfaction. But the milk of an animal will only cause [susceptibility to] tumah [if its emergence is] to [one’s] satisfaction. R’ Akiva said: The matter [can be proven through] a kal vachomer: For if the milk of a woman, which is intended only for chil-dren, will cause [susceptibility to] tumah [whether its emergence was] to [one’s] satisfaction or [was] not to [one’s] satisfac-tion, [then] animal milk, which is intended for both children and adults, is it not logical that it should cause [susceptibility to] tumah [regardless of] whether [its emergence was] to [one’s] satisfaction or [was] not to [one’s] satisfaction? [The Sages] said to him: Not so. For if the milk of a woman that [did] not [emerge] to [one’s] satisfaction generates [susceptibility to] tu-mah, [it is] because the blood of her wound causes [susceptibility to] tumah; will the milk of an animal that did not [emerge] to [one’s] satisfaction [likewise] generate [susceptibility to] tumah, when the blood of its wound does not cause [susceptibil-ity to] tumah? [R’ Akiva] said to them: I am more stringent regarding milk than [I am] regarding blood! For if one expresses milk for therapeutic reasons, [the milk] will cause [susceptibility to] tumah; but if one lets blood for therapeutic reasons, [the blood] will not cause [susceptibility to] tumah! [The Sages] said to [R’ Akiva]: [The law concerning] baskets of olives or grapes will serve as proof: For if liquids ooze from [the baskets] to [the owner’s] satisfaction, they will cause [susceptibility to] tu-mah; but if [liquids ooze] not to his satisfaction, they will not cause [susceptibility to] tumah. He said to them: Not so. If you say thus concerning baskets of olives and grapes, [it is] because in the beginning [the fruits] were a food and in the end [the liquid that oozes] is a beverage; will you say [the same] concerning milk, the beginning and the end of which was a beverage? Until this point was the response. R’ Shimon said: From here on, we would answer in his presence [as follows]: Rainwater will serve as proof, since in the beginning and in the end [it is a] beverage, and yet it does not cause [susceptibility to] tumah unless it emerged to [one’s] satisfaction. He said to us: Not so. If you say thus concerning rainwater, [it is] because the ma-jority [of rainwater] is not for [the benefit of] people, but for [the benefit of] land and trees; but the majority of milk is for [the benefit of] people.