Non-nano zinc oxide is recognized for its safety when used on the skin. It acts as a barrier against harmful UV rays, helping to protect the skin from potential sun damage. Commonly used in various sunscreens, non-nano zinc oxide sits on the surface of the skin, providing a protective layer that helps to prevent sunburn. Its application is non-invasive, as it does not penetrate deeply into the skin, making it a preferred choice in sunscreen.

Source(s):

https://pubmed.ncbi.nlm.nih.gov/20354643/