How Semi-Permanent Sunscreen Will Work

Sunscreen is a summer essential for avoiding burns and cancer risk, but it’s far from perfect. It can rinse off when exposed to water or sweat, leaving your skin vulnerable, and it can be absorbed into the skin. A Yale dermatologist has developed a sunscreen that sticks to the skin, rather than soaking into it. Though this new sunscreen is still being tested, it has the potential to offer sunbathers a safer, more effective way to stay safe from the sun’s harmful rays.

Sunscreen is very effective at protecting skin from the sun, but it also carries certain risks. Some of the molecules in sunscreen that absorb UV radiation can make their way into the skin and then into the bloodstream. According to Scientific American, “There is no evidence that these absorbing molecules can directly harm humans.” However, there has been some research to suggest that these molecules can “bind to hormone receptors” and disrupt normal hormone function, and that, when UV light interacts with certain UV filters in sunscreen, a reaction occurs that has the potential to cause cell damage. Although research on these potential risks is still ongoing, scientists at Yale University decided to get around the whole issue of sunscreen leaching into the skin by creating a new type of sunscreen — one that doesn’t absorb into the skin at all.

Dermatologist Michael Girardi teamed up with Yale’s bioengineering department to create a sunscreen that sits on top of the skin instead of being absorbed into it. In this new sunscreen, a UV filter is encased in bioadhesive nanoparticles that bind to proteins on the skin. The nanoparticles prevent any chemicals from being absorbed into the skin, and they are sticky — so sticky that, in a test using mice, the sunscreen stayed on the skin for days at a time. The study, published in Nature Materials , also found that the new sunscreen is as effective at blocking UV rays as commercially available sunscreens, despite the fact that it contains a much lower concentration of UV filters.

This new sunscreen formula offers a number of potential benefits, beyond keeping UV filters and other chemicals out of the bloodstream. It doesn’t come off with water (in fact, the best way to remove it is to slough it off by rubbing the skin with a towel), so wearers won’t have to worry about reapplying when out at the beach or pool. Yale Scientific reports that, because this formula isn’t absorbed into the skin, there’s also less danger of the sunscreen causing allergic reactions or skin irritation.

This adhesive sunscreen is still in development, and it could be a while before you see it on store shelves. In the meantime, don’t skip out on regular sunscreen, regardless of potential risks related to skin absorption. Whatever these risks may be, they are still a lot less dangerous than exposing unprotected skin to UV radiation. “The last thing I want is people to stop using sunscreen and, [as a result], suffer from more damage,” Girardi told Yale Scientific. So keep packing on that SPF, and don’t forget to reapply.

Images: Jade0626/Pixabay; Filipp Nekhaev/Unsplash