I just had to come back and add a few more comments.
I think that as black women, we are the most diverse group of creatures to ever walk this earth. We come in a variety of different shapes, sizes and colors, and each of us is very unique. Being a black women, we have so many options as to what to do with our hair, which is what makes being a black woman so wonderful. I believe our personality speaks through our hair. If one chooses to relax their tresses, "lock 'em up", or just let it curl up, we must respect each other's choice. Just because a woman chooses to get a relaxer doesn't make her any more/less black than the woman who chooses to wear afro puffs.
There is chemical and disease engineering going on everywhere. Unless you are a hermit, living in the back hills of Kentucky somewhere, growing and herding your own food, you are subject to some kind of "exposure" to unknown chemicals. It's everywhere - who knows, maybe not only your relaxers but your shampoo and conditioners!!
All I really want to say is that hair is a form of expression in some respects. Whether you choose to go straight, go natural or go jheri curl, it's all about you!! Period.