The dual challenge of FDA-evaluated non-GRASE UV filters: Photostability and systemic absorption - A path toward...

Category III Non-GRASE (Generally Recognized as Safe and Effective) UV filters (UVFs), such as avobenzone, octocrylene, oxybenzone, octinoxate, octisalate, and homosalate, face two significant challenges: photodegradation and systemic absorption. Many of these UVFs break down when exposed to sunlight, reducing their effectiveness and generating potentially harmful byproducts which will absorbed by the body. Researchers have developed various stabilization strategies to address these challenges and enhance UVF performance while minimizing health risks. Encapsulation techniques, such as embedding UVFs in silica, liposomes, and polymer matrices, help reduce systemic absorption while maintaining UV protection. Nano-Hybrid organic-inorganic formulations, a nano-scale version of pairing between organic and inorganic UVFs, have also shown promise in improving photostability and preventing degradation. Additionally, polymeric UVFs and controlled-release systems offer long-lasting sun protection, ensuring that the active ingredients remain effective over time. Multi-phase emulsions and layered sunscreen formulations further reduce photodegradation, providing more stable and reliable UV protection. With increasing regulatory scrutiny and growing concerns about environmental and human health impacts, this review explores the dual challenge (balancing stability and safety) faced by non-GRASE UVFs. By integrating advanced materials and innovative formulation technologies, next-generation sunscreens have the potential to deliver superior photoprotection while being safe to human.