A partial answer ...
There are actually only 12 impurities of a human body.
Blood, tears, ear wax, phlegm, sweat, urine etc are considered as the 12 impurities of the human body as per Manu Smriti.
See the following verses:
Manu Smriti 5.134. In order to cleanse (the organs) by which urine and
faeces are ejected, earth and water must be used, as they may be
required, likewise in removing the (remaining ones among) twelve
impurities of the body
Manu smriti 5.135. Oily exudations, semen, blood, (the fatty substance
of the) brain, urine, faeces, the mucus of the nose, ear-wax, phlegm,
tears, the rheum of the eyes, and sweat are the twelve impurities of
human (bodies).
Now, from this page we get the commentary of Medhatithi on 5.135 (mentioned as 5.133 in the linked page). From there we also get to know about a similar verse found in Vishnu Smriti.
Viṣṇu (22.81).—‘Adeps, semen, blood, dandruff, urine, faeces, ear-wax,
nail-parings, phlegm, tears, rheum, and sweat are the twelve impure
excretions from the body.’
And, Atri Smriti too has a similar verse:
Fat, semen, blood, marrow, urine, excreta, dirt of the ears, nails,
phlegm, bones, dirt of the eye, and drops of perspiration, these
twelve are the dirts of men.
Atri Smriti 1.31