Earwax in the canal. Jaw movement assists this process by dislodging debris attached to the walls of the ear canal, increasing the likelihood of its expulsion. The lubrication provided by cerumen prevents desiccation of the skin within the ear canal. The lubricative properties arise from the high lipid content of the sebum produced by the sebaceous glands. In wet-type cerumen, these lipids include cholesterol, squalene, and many long-chain fatty acids and alcohols. While studies conducted up until the 1960s found little evidence supporting antibacterial activity for cerumen, more recent studies have found that cerumen has a bactericidal effect on some strains
Body substance isolation Body substance isolation Body substance isolation is a practice of isolating all body substances (blood, urine, feces, tears, etc.) of individuals undergoing medical treatment, particularly emergency medical treatment of those who might be infected with illnesses such as HIV, or hepatitis so as to reduce as much as possible the chances of transmitting these illnesses. BSI is similar in nature to universal precautions, but goes further in isolating workers from pathogens, including substances now known to carry HIV. Practice of Universal precautions was introduced in 1985–88. In 1987, the practice of Universal precautions was adjusted by a set of rules