I highlight my hair. I don't dye it fully, only because its way too much effort to keep it dark. (I usually get colour in my hair two or three times a year). I get it professionally done with a woman who uses the dye that's approved by doctors (or the cancer society. I'm totally drawing a blank).
If you're concerned, talk to a professional hair stylist if you're able. I have asked my hair stylist for the brand again, and will pass it along when she replies.