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Question: What is earwax and why does it form?
Earwax is produced by two types of glands: modified sweat glands called ceruminous glands, and sebaceous or oil glands. The secretions from the ceruminous and sebaceous glands, both cerumen and sebum, combine to form what we call earwax.
Earwax is composed of more than 40 different substances including not only wax and oil but also dead skin cells. In fact, the primary component of earwax is keratin, an extremely fibrous protein substance found in the outermost layer of the skin. On all other parts of the body, old dead skin cells are removed by friction such as during bathing or from contact with clothing; but in the ear, earwax performs this important function. The movement during chewing, swallowing, and talking as well as small hairs called cilia help to move the earwax and debris (old skin cells, dust, or dirt) to the external opening of the ear; thus earwax traps dust and dirt, and it cleans and lubricates the ear canal as it migrates from the eardrum to the outer ear.
The exact composition of earwax varies from person to person and ranges in color from golden-yellow to tan to dark brown or even black. Scientists have not yet discovered exactly what pigment is responsible for giving earwax its color. What scientists do know is that there are essentially two types of cerumen-dry and wet-and which type a person has is genetically determined. Scientists believe that the type of earwax is coded for by a single gene. The trait for the dry type is recessive while the trait for the wet type is dominant. Dry earwax is more common in individuals of Asian and Native American descent whereas wet earwax is more common in African Americans and Caucasians. Wet cerumen can be further classified as soft (moist and sticky) or hard (dry and desiccated). Soft cerumen is more common in children and hard cerumen is more common in adults.
Sometimes too much earwax builds up in the ear, and can then harden and cause a blockage in the ear. People with hard cerumen are more likely to have problems with it accumulating and occluding the ear canal; hence, cerumen impaction is a common problem in the elderly. When cerumen becomes impacted, a person may experience ear pain or have problems with hearing. Treatment for cerumen impaction involves either irrigations of the ear with solutions that can dissolve the earwax or removal of the earwax with blunt instruments. These procedures should be performed only by individuals who are trained to do so. Many people use cotton swabs to remove earwax from their ears. While cotton swabs are okay to use on the outer ear, they should NEVER be used to remove earwax from the ear canal. Using cotton swabs actually increases the risk of earwax impaction by pushing it further into the canal. Moreover, using cotton swabs in the ear canal can damage the cilia, tear the skin increasing the risk for infection, and seriously injure the eardrum.
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