As their name suggests, nanoparticles are extremely small molecules that are added to skincare products and cosmetics to change the function of an ingredient and enhance delivery mechanisms of active ingredients. Studies have shown that these particles can be absorbed more easily into the skin and may pose serious risks to both human and environmental health. The most common nanoparticles are titanium dioxide and zinc oxide, used in some sunscreens. While these ingredients could prove amazing results in skincare technology, more research is needed to confirm that they are safe.