TiO2 Nanoparticles as a Common Component of Sunscreens: An Experimental Study of Dermal/Ocular Safety Assessment

The safety evaluations of sunscreens containing Titanium Dioxide-Nanoparticles (TiO2-NPs) were done by dermal exposure, acute dermal and eye irritation/corrosion, and skin sensitization according to the guideline for Organization for Economic Co-operation and Development (OECD). The aim of our study was the evaluation of safety and toxicity of TiO2-NPs following acute sunscreen exposure. TiO2 and TiO2-NPs (20-40 nm and 98% purity) were purchased in the anatase crystal phase, and five types of concentration for sunscreens were made which were carried out in five different treatment groups in mice and rabbits. In acute eye irritation using rabbits, the only irritation effect was observed in the conjunctivae area within one hour after administration both in TiO2-NPs group and TiO2-Ps. In acute dermal irritation using rabbits did not show a significant difference among groups in different concentrations and durations. Similarly, in a skin sensitization test using mice, contact hypersensitivity (CHS) did not show a significant difference (P<0.05) among groups in 15% concentration of TiO2 in the different durations after application. Our finding demonstrates that TiO2-NPs and TiO2-Ps in sunscreens are relatively safe and did not induce statistically significant eye and dermal irritation and skin hypersensitivity