(Washing your hair with water containing the metal can lead to split ends and unmanageable hair. The metal gradually builds up in in the outer layers of the hair, helping to speed up damage caused by sunlight, causing split ends, fly-away strands and less shine. The effect is even more pronounced in those who use hair dye.
The research, published in the International Journal of Cosmetic Science, says that treating hair with chemicals more commonly used in washing powder, known as chelants, could reduce the action of the copper.
I really can't imagine washing my hair in Daz, so maybe the answer is to wash your hair less, and let it grow naturally grey.)