Investigation of age, sex and menstrual stage variation in human cerumen lipid composition by high performance thin...

The objective of the study was to correlate quantitative changes in the lipid composition of human cerumen with changes in age, sex and menstrual cycle stage.

Cerumen samples were collected from the external ear canal and analysed using sequential, one dimensional, high performance thin layer chromatography.

The following age groups of both sexes were investigated: one to 10 years; 11-18 years; 19-40 years; and 40 years and over. Additionally, cerumen samples from subjects in three stages of the menstrual cycle were compared.

In the cerumen samples, the peak values for wax ester and cholesterol occured between the ages of one and 10 years for both sexes. However, squalene and triglyceride content reached maximum levels at puberty. Men aged 19-40 years had a significantly greater percentage of cerumen lipid squalene content than women from the same age group; however, their cholesterol content was found to be lower. Regarding the various menstrual cycle stages, cerumen samples taken at the follicular stage from women aged 19-40 years had a significantly lower free fatty acids content, and higher cholesterol and squalene levels, compared with samples taken in the luteal or menstrual stages.

The proportions of the lipid constituents of cerumen varied with age, sex and menstrual stage. In cerumen, the main lipid constituent stimulated at puberty appears to be squalene, not wax esters as reported for sebum. The relevance of lipid constituents to cerumen's protective role is discussed.