Green Hair
This condition is always associated with copper in some form and tends to affect repeatedly bleached hair. It is never seen in black hair, as the green becomes lost in the background color. It may come from swimming pool water, especially where chloride treatment or copper algicides are used. Interestingly, it may be the result of high levels of copper in pipes in the home. This may have come from the water company's treatment plant, or from new copper piping in the house. In a house that has both old iron water pipes and new copper ones, there may be hugely increased copper levels in the drinking water. Green hair can even follow a good long soak in a bath that has been cleaned with old bathroom cleaners containing high chloride levels! And just occasionally it is the result of using a bleach.
Using a lemon juice rinse may improve the color. There are commercial products that can help: an experienced hair stylist can advise on which might be used.
