I've done the clay baths twice. (Kinda bothersome since I have a jetted tub so I have to line it with plastic and then bail out the water into the toilet.)But well worth the trouble. Results in a great night's sleep and happy skin. Also did a foot soak one time too - HappyFeet! There was a definite darkening of the clay so I'm sure that something nasty was leached out of me. I haven't seen anything negative published anywhere about clay baths. Happy soaking! Oh yeah, don't soak for longer than advised (at least the first one) because they do take more out of you than a regular soak.
Jay