Why is my hair green after swimming?

Dear Jenni, 

Swimming pools aren’t just pure water; they also contain chemicals like chlorine and copper to sanitize the water and break down algae. While these aquatic organisms are often harmless, chemicals to control their levels are used in pools because algae attract bacteria that are harmful to humans. The downside of these chemicals is that they can cause irritation to skin and hair and, as you’ve experienced, even change the color of your hair. For more information about the effect of copper and chlorine on hair, and treating green-tinged tresses, swim along in this pool of knowledge. 

Why does hair turn green after swimming?  

Have you ever wondered why pennies sometimes turn green? It’s actually similar to why your hair turned green after swimming! The culprit is oxidized copper. Hair is quite absorbent, so it readily takes in the high levels of oxidized copper from the pool water. Hair naturally contains some copper, but the excess copper is what changes the color. 

While this phenomenon happens to all hair colors, it’s more visible on lighter hair shades, like your blonde locks. In fact, if your hair isn’t naturally blond but bleached, it might be more susceptible to color change. Additionally, chemical straightening, perming, and exposure to UV light can also leave your hair more vulnerable to changing color.  

What can you do to prevent green hair?  

Going green is applaudable when it comes to the environment, but you might not want your hair to follow suit. Luckily there are some things you can do to prevent your hair from turning green: 

• Pre-wash: since hair is absorbent, you can get your hair wet before swimming. By doing this your hair soaks up the pre-swim water instead of the swimming pool water.
• Apply protective coating: putting conditioner or oil specific for hair on your hair can help prevent chlorine from being absorbed and damaging your hair.  
• Don a cap: swimming caps cover your head, blocking any water from touching your hair and thus protecting it from any copper damage.
• Wash immediately: make sure to rinse your hair right after swimming so that the chemicals aren’t sitting on your hair. 

What can you do to treat hair that’s already green?  

If your hair’s green, don’t be blue! Hair that’s already been exposed to oxidized copper can still be salvaged. You can try mixing some baking soda into your shampoo or washing your hair with apple cider vinegar diluted with warm water. While these homespun potions will neutralize the green color, they may also dry your hair out. That’s why it’s important not to overuse these concoctions. Adding a rich conditioner into your routine can help replenish the moisture in your hair. 

How else can swimming damage hair?  

Unfortunately, chlorinated water can leave hair dry and damaged. Chlorine strips lipids from hair. This is noteworthy because these lipids naturally coat our hair to help it retain moisture and prevent any foreign material from penetrating it. Without lipids, hair can become dry. Chemicals in swimming pool water can also change the protein structures in hair, like keratin. The loss of such important proteins can weaken and damage hair fibers.  

How else can swimming impact your body?  

It’s not just hair that’s affected from exposure to chlorine—your skin can also become irritated. In particular, your skin might become: 

• Dry and rough: chlorine strips the natural oils from skin, which can result in dryness and irritation. 
• Pimple-prone: because chlorine strips the skin’s natural oils, the skin might overproduce sebum as compensation. As a result, breakouts can occur. 
• Prematurely aged: chlorine exposure also leaves skin more susceptible to UV damage via tanning and sunburn. This, along with chlorine’s breakdown of collagen (which keeps skin firm), puts skin at risk for wrinkles.  

You can prevent skin damage through techniques similar to the hair damage prevention tips already mentioned. For example, shower before entering the pool as wet skin absorbs less chlorinated water. You can also spread a light layer of oil on your skin to act as a protective barrier against chlorine penetrating the skin. Additionally, limiting your time in the pool and wearing sunscreen can also be helpful. After swimming, you can rinse the chlorine off immediately and follow that up with a rich moisturizer to help remedy any dryness.  

Hope this helps you just keep swimming!