Nanomaterials In Sunscreens Engineered nanomaterials are widely used in sunscreens to make sun-blocking ingredients like titanium dioxide and zinc oxide rub on clear instead of white. These materials have been shown to exhibit different fundamental physical, biological, and chemical properties than their larger counterparts. The report indicates that very few nanomaterials have been adequately tested, though the limited data that is available shows that their small size makes them more able to enter the lungs, pass through cell membranes, and possibly penetrate damaged or sunburned skin. Want to read more? Subscribe to one of our monthly plans to continue reading this article.