Here are some questions and answers on the effect of the chlorinated water we swim in every time we dive into a pool:

Q: Can chlorine in pool water cause my hair to turn green?

A: Too much chlorine in the water does not cause blond, gray or white-haired swimmers' hair to turn green. Exposure to hard metals dissolved in the water -- particularly copper, iron or manganese -- is really to blame.

Q: When absorbed by the hair shaft and oxidized by chlorine, metals commonly found in pools tend to leave behind a greenish residue on hair.

A: Metals are introduced into pool water through source water used to fill the pool, as algaecides or sanitizers, from ionizers, as a result of electrolysis, from water moving through recirculation pipes at excessive velocities, and from maintenance of aggressive (acidic) water conditions in the pool.

You can help reduce the build-up of metals and remove some oxidized metals from your hair by using shampoos which contain the chelating agent EDTA (ethylenediamene tetracetic acid). Washing your hair in warm water containing dissolved aspirin will have a similar result.

Also, monitor the amount of dissolved metals in the water, and add sequestering or chelating agents to the pool to neutralize or remove metals from the water before they have a chance to be absorbed by your hair.

Q: Can swimming in chlorinated pools damage or bleach my hair?

A: Swimming in chlorinated pools can severely damage hair, and damage can be cumulative. The longer or more frequently you swim, the more damage. Chlorine is a bleach and it will cause hair pigment to lighten. Color-treated hair may fade, and darker hair may become less shiny.

Permed hair -- which is already porous and protein-damaged as a result of chemical treatment -- will tend to absorb chlorine, becoming further damaged and overprocessed.

Chlorine bonds with hair protein and causes the cuticle, the protective scaly outer protein layer that covers the inner cortex and central medulla of each visible hair shaft, to be eaten away resulting in dry, brittle, straw-like, damaged hair.

Chlorine will make the hair shaft weak and easily damaged by brushing or combing, and hair breakage and split ends may result. Some long distance and competitive swimmers have even reported losing their hair in patches.

Q: What can I do to protect my hair from damage caused by swimming in chlorinated pools?

Rinse your hair with fresh water immediately after swimming and don't allow chlorine to dry on your hair. Wash your hair when you're finished swimming with a shampoo which is designed to repair damage caused by swimming in chlorinated pools.

Look for a shampoo which is pH balanced, contains sodium thiosulfate to dissolve chlorine, and which will replace protein eroded by chlorine exposure. Don't brush your hair when it's wet. Let it dry naturally, then brush only with a wide-toothed comb to lessen the chance of breakage.

Try to limit the use of blow dryers, electric curlers and curling irons -- they further dry out already dry hair.

Damaged hair can be partially repaired by conditioning while you swim. Before beginning a workout, apply a protective conditioner to your hair and cover it with a latex or silicone bathing cap. Heat generated during water exercise or swimming will provide a heat-conditioning treatment.

Wearing a conditioner while swimming will also prevent chlorine from being absorbed into, and damaging your hair, in the first place.

For more information, contact Dr. Alison Osinski of Aquatic Consulting Services: (619) 270-3459.