I had to google it - Wiki so must be true;
Nasal sebum, also known as nose grease/oil, is grease removed from the surface of the human nose. The pores of the lateral creases (where the nose joins the face) of the exterior of the nose create and store more oil and grease than pores elsewhere on the human body, forming a readily available source of small quantities of grease or oil. The grease is a particularly oily form of sebum, thought to contain more squalene (C30H50) than the secretions from other parts of the skin.[citation needed] It is notable because nose grease is a convenient durable lubricant.