Attachment 3 Uv-a Protection with New Class of Uv Absorber

The Sun Protection Factor (SPF) measurement is based on erythema; mainly caused by Ultraviolet B radiation (UV-B). Therefore, SPF more appropriately describes a Sunburn Protection Factor. On the other hand, the awareness for the need of protection against W-A radiation is rising and the claim for W-A or broadband protection can already be seen on sunscreen bottles around the world. Several in vivo and in vitro methods to assess the W-A protection are available. However, the availability of efficient and photostable W-A absorbers is far from ideal. With the new W-A-absorber Ciba@ TINOSORBTM M, the formulator is offered a Wfilter that fulfills the need for better WA protection. TINOSORB M defines a new class of W absorber; consisting of microfine, organic particles, combining the best of the two conventional categories; chemical/soluble and physical/insoluble. TINOSORB M does indeed combine the best of both worlds. As a particle, it provides W protection by reflection and scattering. Furthermore, classical absorption plays an important role due the organic nature of the substance. In this paper the high efficacy and exceptional photostability of this new WA filter is shown and the incorporation into sunscreen formulations is discussed. Background of photo protection Solar radiation in the range of infrared is perceived as heat, in the visible as color, and in the ultraviolet as the result of photochemical reactions. Such photochemical reactions may ultimately stimulate melanin production and tanning, or lead to genetic mutatins and to aberrant cell behavior. The fact that the radiation energy increases with the decrease of the wavelength, and that longer waves are less reflected by an object holds also true for UV-radiation. Short wave W-radiation is more likely to induce photochemical reactions. Long wave W will penetrate deeper into the skin. Hence, the biological effects induced by W-radiation changes with the wavelength. UV-B (wavelengths between 290 nm 320 nm) W-B radiation stimulates the production of Vitamin D. It affects especially the epidermal layer of the skin, where it causes Erythema (sun burn). Frequent and intense exposure to UV-B induces lesions on the DNA and suppresses the immune response of the skin. In turn, W-B enhances the risk of fatal mutations eventually leading to skin cancer and reduces the chance that a malignantly transformed cell is recognized and destroyed (1).