Particles with at least one dimension between 1 and 100 nanometers, which are too small to be seen with the naked eye or conventional microscopes.
Since they do not reflect visible light, nano-sized titanium dioxide and zinc oxide particles are used in sunscreens to scatter UV rays without causing a white coating.
Nanoparticles are occasionally produced in nature or can be engineered for commercial purposes.
Consumer concerns and what we know
A common concern is that nanoparticles could penetrate the skin and end up in internal organs or the bloodstream – and that they may be toxic. The European Commission found that nanomaterials do not penetrate into healthy skin and are therefore considered safe. However, the safety of particles inhaled from powder or aerosol products has not been verified.
Nanomaterials are permitted worldwide. In some countries and regions including Europe, the word 'nano' must follow the name of the substance in ingredient listings (in parenthesis).
We use titanium dioxide and zinc oxide nanoparticles in sunscreen products due to their highly performing properties. We have evaluated that they do not penetrate the skin, and since they are generally suspended in wet formulas (emulsions, solutions, etc.), the risk of inhaling them is low. Furthermore, we have assessed that the potential amount that could be inhaled does not represent a risk to human health.