What causes black dyed hair to turn green?

There are a few reasons why black dyed hair may turn green.

* Chlorine. Chlorine is a common chemical found in swimming pools and some tap water. It can react with the pigments in black hair dye and cause it to turn green. This is especially likely if the hair is porous or damaged.

* Copper. Copper is another metal that can react with black hair dye and cause it to turn green. Copper is found in some water pipes and can also be present in hair products.

* Hard water. Hard water contains high levels of minerals, such as calcium and magnesium. These minerals can build up on the hair and cause it to look dull and greenish.

* UV radiation. UV radiation from the sun can also cause black hair dye to fade and turn green. This is why it's important to protect your hair from the sun by wearing a hat or scarf when you're outdoors.

If your black dyed hair has turned green, there are a few things you can do to try to fix it.

* Wash your hair with a clarifying shampoo. A clarifying shampoo will help to remove any build-up of minerals or product from your hair.

* Use a purple shampoo. Purple shampoo is designed to neutralize yellow tones in hair. It can also help to correct green tones.

* Apply a deep conditioner. A deep conditioner will help to hydrate and nourish your hair, which can help to improve its overall appearance.

* See your hairstylist. If you can't fix the green tint in your hair yourself, you may need to see your hairstylist. They may be able to use a professional color treatment to correct the problem.

To prevent your black dyed hair from turning green in the future, you can take a few precautions:

* Avoid swimming in chlorinated water.

* Use a shower filter to remove copper from your water.

* Rinse your hair with cool water after shampooing and conditioning.

* Protect your hair from the sun by wearing a hat or scarf when you're outdoors.

* Use a leave-in conditioner or hair oil to help keep your hair hydrated and healthy.