THE STATE OF NANO-SIZED TITANIUM DIOXIDE (TIO2) MAY AFFECT SUNSCREEN PERFORMANCE.

• TR Number: 689
• Keywords: EPI-200-X, Nanoparticles, Nanoproducts, Permeability devices, Permeability enhancers, Sodium fluorescein, Sunscreen, TiO2 (80% anatase, 20% rutile) uncoated, TiO2 (rutile) coated, TiO2 (rutile) submicron, Titanium dioxide (TiO2), UV exposure

In the past several years, there has been a trend in the sunscreen/cosmetics industry to replace micron-sized titanium dioxide (TiO2) particles with nanoscale materials. The increased use of nanoscale TiO2 has resulted in questions about these and other nanoproducts. This study examines the effects of using nanoscale TiO2 on ultraviolet (UV) attenuation in simple to complex sunscreen formulations. UV light attenuation, product stability, and potential damage to the skin barrier were examined with both nanoscale and microscale TiO2 particles. Results indicate that none of the formulations decreased the barrier function of the skin and the best UV attenuation occurs when the TiO2 particles are stabilized with a coating and evenly distributed such as with non-agglomerated coated nanoscale materials. This indicates that nanoscale TiO2 may have better efficacy while lacking toxicity.