Titanium Dioxide
Also known as: TiO₂, CI 77891
Description
Titanium dioxide is an inorganic (physical/mineral) UV filter and one of only two FDA Category I sunscreen actives classified as GRASE (Generally Recognized as Safe and Effective). It provides primary protection against UVB and short-wave UVA (UVA II) radiation, with diminishing efficacy in the long-wave UVA (UVA I) range. Micronized and nano-sized forms are commonly used to reduce the characteristic white cast while maintaining photoprotective efficacy. Titanium dioxide is photostable and does not degrade under UV exposure, making it a reliable broad-spectrum filter when combined with UVA boosters. Its inert nature and minimal irritation potential make it particularly well-suited for sensitive, rosacea-prone, and post-procedural skin. [Smijs 2011]
Mechanism of Action
Titanium dioxide protects against UV radiation through a combination of scattering, reflection, and absorption of UV photons. In its rutile crystalline form, it absorbs UV radiation in the 290–350 nm range (UVB and UVA II), while also physically scattering photons away from the skin surface. Micronized particles (10–50 nm) shift the dominant mechanism toward absorption rather than scattering, improving cosmetic elegance. TiO₂ remains on the skin surface with negligible percutaneous penetration, resulting in a favorable safety profile. It does not interact with biological targets and has no known systemic pharmacological activity, making it one of the safest UV filters available. [Serpone 2007]
Indications
- UVB and short-wave UVA protection [Smijs]
- Sensitive skin sun protection [Schneider]
- Rosacea-prone skin sun protection [Smijs]
- Post-procedural photoprotection
- Pediatric sun protection
- Pregnancy-safe sun protection
Available Concentrations
Side Effects
- White cast (especially at higher concentrations and on darker skin tones) [Smijs]
- Potential dryness with prolonged occlusive use [Schneider]
- Rare contact dermatitis or irritation
- Cosmetic inelegance in tinted formulations if poorly dispersed
Contraindications
- Known hypersensitivity to titanium dioxide (extremely rare)
- Inhalation risk with loose powder formulations (avoid aerosolized application)
Pregnancy Category
FDA Category I sunscreen active (safe — no systemic absorption)
Found In
Cosmetics containing Titanium Dioxide
Related Conditions
References
- Schneider SL, Lim HW. "A review of inorganic UV filters zinc oxide and titanium dioxide." Photodermatol Photoimmunol Photomed, 2019. doi:10.1111/phpp.12439
- Serpone N, Dondi D, Albini A. "Inorganic and organic UV filters: their role and efficacy in sunscreens and suncare products." Inorganica Chimica Acta, 2007. doi:10.1016/j.ica.2006.11.011
- Smijs TG, Pavel S. "Titanium dioxide and zinc oxide nanoparticles in sunscreens: focus on their safety and effectiveness." Nanotechnol Sci Appl, 2011. doi:10.2147/NSA.S19419
Limitations
This page provides a general overview of Titanium Dioxide in dermatology. It does not cover every possible use, formulation, or interaction. Individual responses to compounds vary — what works for one person may not work for another. Always consult a qualified dermatologist before starting or changing any treatment.