Nanoparticles are used in SPF, lotions, and a variety of other body care products. You won’t find the label “nanoparticles” used; you will usually find them labeled as nanonized zinc, nanonized titanium, etc. Because it is an expensive technology, they are generally found in high-end brands. lThey have been shown to be easily absorbed into the body, breaching the dermal layer. They are barely (if at all) regulated and almost never labeled.  Particles of such small size also come with the risk of carrying other dangerous particles with them. We believe much more testing must be done, since ingredients at nano-size may behave differently than larger-scale ingredients of the same molecular structure.