whateveryo saidFrom doing a bit of research the worst sulphates can do is over strip your scalp/hair making them dry/brittle or making your hair color fade faster.
There is no study that I've seen that links it to the development of cancer.
Sodium lauryl sulfate used in the majority of shampoos is very mild.
The most violently irritating personal care product I have ever used was a soap-based shampoo from Aubrey Organics. No matter how tightly I kept my eyes closed, it would seep in, sting like hell, and make my eyes solid bloodshot red. On top of that, it left my hair feeling like straw.
There are similar surfactants to SLS that are gentler, like sodium olefin sulfonate and sodium laureth sulfate, and those are the ones commonly found in higher quality shampoos. Look at the shampoos in a health food store, and the ones from Aubrey Organics will most likely be the only ones based on soap; most hippie-brand shampoos use the gentler SLS alternatives.