Zinc Oxide (Nano)
Zinc Oxide (CAS 1314-13-2) is an inorganic (physical) sunscreen agent that provides broad-spectrum UV protection spanning UVB, UVA II, and UVA I almost uniformly, making it the broadest-range sunscreen available. It is also classified as a skin protectant and is used in formulations addressing skin irritations such as diaper rash. In nano form, it reduces the characteristic white cast on skin; current research indicates nanoparticles remain on the skin surface or in the uppermost dead layer and are not absorbed into living tissue.
Zinc Oxide offers the broadest UV spectrum protection of any single sunscreen ingredient, covering UVB, UVA II, and UVA I. It is highly stable, non-irritating, and functions as a skin protectant and anti-irritant. Its nano form improves cosmetic elegance by reducing the white cast while maintaining surface-level safety.
Not to be used in applications that may lead to inhalation exposure (EU Cosmetic Restriction IV/144). Nano form carries theoretical health concerns if absorbed, though current evidence shows nanoparticles do not penetrate beyond the uppermost dead skin layer. Multiple SCCS opinions and EU restrictions apply; formulators should consult current regulatory guidance.
