This review critically evaluates the sunscreen delivery and toxicity field. We chose to focus on approved sunscreens in this review. Optimal sunscreen use prevents skin cancer and photoageing but there is an important knowledge gap in sunscreen/skin interactions. Sunscreen delivery is a key for efficacy, but studying sunscreen delivery is not straightforward. We review the strengths and weaknesses of in vitro, excised skin and clinical approaches. Understanding positive and negative sunscreen effects on skin homeostasis is also challenging. The results in this field, especially in vitro testing, are controversial and experimental design varies widely which further supports disparities between some findings. We hypothesize that bias towards showing sunscreen toxicity to increase impact could be problematic. We explore that perception through a detailed review of experimental design, especially in cell culture models. Our conclusion is that emerging, non- and minimally invasive technologies are enabling new approaches to volunteer studies that could significantly improve knowledge of sunscreen delivery and interactions.

这篇综述批判性地评估了防晒霜的传递和毒性领域。在本次审查中，我们选择专注于批准的防晒霜。最佳防晒霜的使用可以防止皮肤癌和光老化，但在防晒霜/皮肤相互作用方面存在重要的知识差距。防晒霜的递送是功效的关键，但研究防晒霜的递送并非易事。我们回顾了体外、离体皮肤和临床方法的优缺点。了解防晒霜对皮肤稳态的正面和负面影响也具有挑战性。该领域的结果，尤其是体外测试，是有争议的，实验设计差异很大，这进一步支持了一些发现之间的差异。我们假设偏向于显示防晒霜毒性以增加影响可能是有问题的。我们通过对实验设计的详细审查来探索这种看法，尤其是在细胞培养模型中。我们的结论是，新兴的非侵入性和微创技术为志愿者研究提供了新方法，可以显着提高对防晒霜传递和相互作用的了解。