Photoprotection: a review of the current and future technologies

Exposure to ultraviolet (UV) radiation is associated with a variety of harmful effects ranging from photoaging to skin cancer. UVB (290 to 320 nm) directly damages the cellular DNA leading to the formation of the 6-4 cyclobutane pyrimidine dimmers, and UVA (320 to 400 nm) indirectly damages the DNA via the production of oxygen radical species. In this review, we focused on the technological and scientific aspects of photoprotection using sunglasses and clothing while attempting to dispel some of the misconceptions. In addition to the basic knowledge relating to sunscreens, we reviewed the current guidelines for testing and labeling UVA protection around the world, controversies associated with nanoparticles, and future sunscreens actives waiting for the Food and Drug Administration approval. Lastly, we reviewed alternative agents, such as antioxidants, that can be used to supplement and augment photoprotection provided by sunscreens.