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
Substance-related disorder Substance-related disorder Substance abuse, also known as drug abuse, is a patterned use of a substance (drug) in which the user consumes the substance in amounts or with methods which are harmful to themselves or others. The drugs used are often associated with levels of intoxication that alter judgment, perception, attention and physical control, not related with medical effects. It is often thought that the main abused substances are illegal drugs and alcohol; however it is becoming more common that prescription drugs and tobacco are a prevalent problem. Substance-related disorders, including both substance dependence and substance abuse, can lead to