passage: Eating mucus -- Mucophagy, despite its benefits on one's immunity, comes with some health risks due to the potential physical aggravation resulting from the action of nose picking, and the germs on fingers and in mucus. Picking one's nose can cause upper airway irritation as well as other injuries including nasal septal perforation (a ``through-and-through defect'' of the cartilage separating the nostrils), and epistaxis (nosebleed). In a study by Andrade and Srihari, 25% of subjects were ailed by nose bleeds, 17% with nasal infections, and 2% with damage more serious than bleeding. W. Buzina studied the fungal diversity in nasal mucus in 2003. 104 samples were gathered with 331 identifiable strains of fungi and 9 different species per patient.