Nanoparticle
Nanoparticle — an extremely small particle, generally defined as measuring between roughly 1 and 100 nanometers in at least one dimension. In skincare, nanoparticles appear in some mineral sunscreens and delivery systems, where their small size can affect texture, appearance, and how ingredients are dispersed in a formula.
Key points
- A nanometer is one billionth of a meter, so nanoparticles are far smaller than what the eye can see.
- Nano-sized zinc oxide and titanium dioxide are used in some mineral sunscreens to reduce the white cast left on skin.
- Regulatory bodies such as the EU require certain nanomaterials to be labeled with the word nano in the ingredient list.
- Current scientific reviews generally indicate that nanoparticles in sunscreen remain on the skin's surface and do not penetrate healthy intact skin.
- Nanotechnology is also explored for encapsulating and delivering active ingredients within formulas.
Frequently asked
Are nanoparticles in sunscreen safe?
Regulatory and scientific reviews generally conclude that mineral sunscreen nanoparticles stay on the surface of healthy, intact skin and are considered safe for topical use, though research continues.
Why are nanoparticles used in mineral sunscreens?
Reducing zinc oxide or titanium dioxide to nano size helps the sunscreen spread more easily and leaves less visible white cast while still providing UV protection.
Related topics
This is a foundational entry in the SYNC Skin Encyclopedia and is expanded over time. Educational information only — not medical advice.
