Scientists at Yale University have been able to develop a sunscreen that will not penetrate the skin, which is a major health concern that is associated with these commercial products. This new sunblock is made with bio-adhesive nanoparticles that will remain on top of the skin's surface without entering. Mark Saltzman the author of this study says, "We found that when we apply the sunblock to the skin, it doesn't come off, and more importantly, it doesn't penetrate any further into the skin. Nanoparticles are large enough to keep from going through the skin's surface, and our nanoparticles are so adhesive that they don't even go into hair follicles, which are relatively open."
The best thing about this new sunblock from the team in Yale is that their product both stays out of the bloodstream and is transparent as well. The same is not true with some sunscreen solutions today that utilize bigger particles of inorganic compounds like zinc oxide and titanium dioxide. That is why the new sunscreen can prove to be the more aesthetic choice if developed further.