Avoid the risk of toxic shock, and care for the environment, with Natracare 100% certified organic cotton, non-chlorine bleached, tampons. Contain no synthetic materials such as rayon or chemical additives such as binders or surfactants. Choose Regular, Super or Super Plus absorbency. A woman may use as many as 11,000 tampons in her lifetime, and rayon and rayon-cotton blends are widely used in tampons. Rayon is commonly chlorine-bleached, and is highly absorbent. Dioxin, a toxic carcinogen, is a by-product of all chlorine bleaching. It collects in fatty tissue, and scientific reports suggest that even low levels of dioxins may be linked to cancer, endometriosis and immune system suppression., she may be subjecting herself to additional dioxin exposure.