filtering showre head?

Basically I am looking for a shower head that may have a filtering device built into it. MY girlfriends sister called me about this. Basically her hair stylist told her she could buy a special shower head that has a filtering device. Essentially the problem is - when blondes dye their hair - certain water can cause the hair to have a greenish hue. If anyone can tell me if they have heard of something like this I would appreciate it. Also if anyone can explain what causes this I would love to know too.

Thanks for any help

Lot's of different ones available.

http://www.google.com/

Ask and ye shall receive : http://www.showerfilterstore.com/

Compliments, this Sunday morning, of the internet Goddess GOOGLE.

It is the chlorine in the water which will affect your hair color, and some folks have skin allergy, so the chlorine filter is what you need.