The basic ingredient of earwax is made by thousands of tiny glands studding the outer walls of the ear canal. These glands produce an oily substance called cerumen, which picks up dead skin cells as it wells out. The end result is what we call earwax.

Earwax starts out pale yellow. But by the time it's ready to fall out, debris-encrusted wax is a dark, crumbling mass.

Since sound waves travel through the ear canal to the eardrum, what's the point of clogging the tunnel? Skin lining the canal is very thin, and dries out easily. Earwax coats the skin, holding moisture in. But earwax also acts as a water repellent.

When shower and pool water run out the way they came in, we can avoid the painful infection known as "swimmer's ear."

Earwax also acts as a sticky trap for anything that blows (or crawls) into the ear. A plug of earwax may contain tiny hairs, teensy bugs, soot, dust, soil and bits of plants. Earwax is the body's fly paper. Older, dirt-laden wax slowly migrates to the entrance of the ear, helped along by jaw movements as we talk or chew.

While the ear is self-cleaning, too much earwax can occasionally build up. Some clues: Sounds seem more muffled. The ear feels stuffed up; the canal itches or aches. As wax presses on nerves, the throat feels tickly, and you may develop a slight cough.

The affected ear may also buzz or ring (a condition called tinnitus), and you may feel dizzy.

While putting a few drops of mineral oil into the ear may help the plug slip out, other home remedies range from useless to dangerous. Cotton swabs can push wax further into the ear; hairpins can puncture the eardrum. Your family doctor can use ear drops and special tools to remove the wax safely.

Why do some people have more waxy build-up than others? Part of the answer lies in human genes. Some people are born with narrower, clog-prone ear canals; some ear canals are especially hairy, and some just make more wax. Intriguingly, humans from different parts of the world have different earwax. People whose ancestors came from Europe or Africa tend to have "wet" earwax, about half fat by weight. People whose ancestors came from Asia, including American Indians, tend to have low-fat "dry" earwax.

Earwax is your friend; squeaky-clean ears actually invite infections. Studies show that fresh cerumen is a natural germicide that can kill staph, strep and E. coli bacteria. So earwax protects the body from intruders trying to enter through a side door.

For more on the stuff in our ears, including close-up photos of earwax in all its yucky glory, visit the Web sites www.tchain. com/otoneurology/disorders/ hearing/wax2.html and http:// medweb.uwcm.ac.uk/otoscopy/ newpage6.htm.

By Kathy Wollard
http://www.nynewsday.com/news/health/ny-hshow4557763dec19,0,2896161.column