This inorganic mineral is used as a whitening (think whitening as in brightening, not as in making dark spots fade) and opacifying agent in cosmetics. Although not considered a primary irritant, it can be poisonous if ingested and is noted for the way it frequently causes skin reactions. This same ingredient is consumed orally before having certain types of X-rays taken; it is believed that barium sulfate’s low solubility and the body’s ability to excrete it both help promote its negligible bioavailability. Still, it’s not the best ingredient to see so prominently in a skin-care product designed to be used around the eyes or on lips (Source: British Journal of Dermatology, September 2004, pages 357–364.)