Sunscreens are topical preparations containing any number of ultraviolet filters (UVFs). The first part of the review will focus on the recent Food and Drug Administration (FDA) regulations of 2019 and general use of these agents. While sunscreen products are becoming more regulated in the United States, we still lag behind other countries in our options for UVFs. Sun protection to prevent skin cancer and aging changes should be a combination of sun avoidance, protective structures, and clothing as well as use of sunscreen products. Newer and safer products are needed to help supplement and replace older agents as well as improve their cosmetic acceptability. This will be a review of ingredients, local toxicities (i.e. contact dermatitis, photocontact dermatitis), special considerations for children, and cosmesis of sunscreen preparations. Part 2 will focus on the environmental, ecological and human toxicities that have been increasingly related to UVFs.

In the United States, the Food and Drug Administration (FDA) regulates sunscreen as an over-the-counter (OTC) drug and not a cosmetic, subjecting it to the agency’s OTC drug review process. In 1999, the FDA published a final set of standards for marketing sunscreens in the United States, called a monograph. Since its publication, the FDA has tried to amend the monograph with little success. Congress has also acted to ease the procedural burdens and hurdles the FDA faces in updating the monograph, but these attempts brought about little change in sunscreen regulations. The United States’ efforts to properly update the standards for sunscreen pale in comparison to other countries, such as those in the European Union and parts of Asia. There, sunscreens are regulated as cosmetics, and new sunscreen ingredients face a different review process, leading to approval of newer and more effective ingredients on an expedited basis. Meanwhile, the FDA has taken a risk-averse approach to sunscreens, and in particular, approvals of new sunscreen active ingredients, as they have consistently denied approvals for new ingredients due to insufficient safety data. This approach has impeded meaningful progress for sunscreens—the last time the FDA approved a new sunscreen active ingredient to be broadly used in sunscreens was in 1999. Some groups support the FDA’s risk-aversion, but others question whether such stringency actually benefits public health long-term. This Note argues that the FDA’s

ABSTRACT Background Skin cancer is the most common cancer in the United States, with over 5 million cases diagnosed annually. Despite being largely preventable, incidence rates continue to rise, largely due to inadequate protection from ultraviolet (UV) radiation, the primary environmental cause of skin cancer. Although global innovation has advanced sunscreen technology, the U.S. regulatory system has not kept pace, limiting public access to more effective UV filters. Methods This review examines the current U.S. Food and Drug Administration (FDA) sunscreen filter regulatory framework, including the Generally Recognized As Safe and Effective (GRASE) criteria and maximal usage trial (MUsT) protocols. We compare U.S. approved filters with newer filters used internationally and analyze barriers to their domestic approval. Results International markets currently use advanced filters such as bemotrizinol, bisoctrizole, drometrizole trisiloxane (DT), and terephthalylidene dicamphor sulfonic acid (TDSA), which offer broader and more stable UV protection. These filters have demonstrated favorable safety and efficacy profiles but remain unavailable in the U.S. due to regulatory inertia. The FDA's new Over‐the‐Counter (OTC) Monograph Order Request (OMOR) process may provide a pathway to modernize sunscreen regulations. Conclusion Modernizing U.S. sunscreen regulations to allow approval of newer, evidence‐backed UV filters is a critical step in improving public health. Broader access t

the availability of advanced sunscreen filters, particularly for low‐income populations who may not have the means to import foreign products. Also, certain populations—especially those with darker skin tones—are often underserved by available U.S. mineral sunscreens, which can leave visible white casts on the skin, further discouraging use. The global availability of more effective and aesthetically pleasing sunscreens from the EU and Asia may exacerbate these disparities unless U.S. regulations are updated to allow for a wider range of effective products. The reliance on older filters, many of which fail to meet their labeled SPF and UVA protection claims, compromises public trust in sunscreen products. Consumers may be unaware that the products they rely on for sun protection are not as effective as those available internationally. This erosion of trust can lead to reduced usage of sunscreens, increasing the risk of skin damage and skin cancer. There is evidence to suggest that the sunscreen filters used in the EU and countries like Korea offer more comprehensive UV protection compared to those approved in the U.S. For instance, Korean sunscreens often utilize filters such as bemotrizinol, bisoctrizole, DT, and TDSA, which provide superior UVA and UVB protection compared to U.S. filters like oxybenzone and octinoxate. This fact, plus the studies showing that U.S. sunscreens fail to meet their labeled SPF and UVA protection factor claims, further emphasizes the need for regulatory updates. 7. Recommendations To ensure that U.S. consumers have access to the best possible sun protection, it is imperative that the FDA modernizes its sunscreen regulations. This could include approving newer filters already in use abroad, such as bemotrizinol, bisoctrizole, TDSA, or DT, which have been shown to provide enhanced protection with minimal systemic absorption. Additionally, the FDA could adopt the PA system, which would offer consumers more information about a product's UV