Episode Summary
Executive Summary: The episode examines the FDA’s approval of BEMT, the first new U.S. sunscreen ingredient in over 20 years, and why that matters for protection, safety, and regulation. Chemist AJ Aday explains BEMT’s broad-spectrum benefits and lower white-cast profile, while journalist Michael Scaturo discusses why U.S. drug-style regulation slowed approval and how sunscreen controversies and animal-testing requirements complicate innovation.
Main Topics: FDA approval of BEMT (Priority: 5/5): BEMT (bimatrizinol) was approved as the first new sunscreen ingredient in the U.S. in more than two decades, marking a major shift in the sunscreen market. How BEMT differs from existing filters (Priority: 5/5): BEMT is an organic UV filter that offers transparent application and strong broad-spectrum UVA/UVB protection, unlike many U.S.-approved filters that skew toward UVB. Sunscreen chemistry and white cast (Priority: 4/5): The discussion explains why mineral sunscreens like zinc oxide and titanium dioxide appear white: visible-light scattering and particle aggregation. Safety and toxicology (Priority: 4/5): BEMT’s larger molecular size may reduce concerns about skin absorption and systemic exposure, and it has undergone extensive safety review. Why U.S. approval took so long (Priority: 5/5): U.S. sunscreens are regulated as over-the-counter drugs, making approval expensive and slow compared with regions where sunscreens are treated as cosmetics. FDA scrutiny and public skepticism (Priority: 4/5): The FDA’s prior findings of small bloodstream absorption from some sunscreen chemicals fueled confusion and skepticism, even though it did not mean the ingredients were proven unsafe.
Key Arguments: BEMT is significant because it is the first organic UV filter in the U.S. with GRAS/E status, expanding options beyond mineral filters. BEMT is especially useful because it efficiently absorbs both UVA and UVB, enabling broad-spectrum protection with fewer ingredients. Compared with avobenzone, BEMT is more efficient because it does not require additional stabilizing filters to work well. BEMT may have a lower biological risk profile because its larger molecule is less likely to be absorbed deeply into the body. White cast in mineral sunscreens comes from light scattering by zinc oxide and titanium dioxide particles, especially when aggregated. The FDA’s slow approval process reflects the U.S. treating sunscreen ingredients as OTC drugs, which increases cost and testing burden. Regulatory caution stems partly from the FDA’s historic desire to avoid harms like those caused by thalidomide, but that caution may now be overly restrictive. Public distrust of sunscreen ingredients increased after FDA blood-absorption tests were misread as a declaration of danger rather than a request for more data.
Data Points: Time since last U.S. UV filter approval: Over two decades - BEMT is the first new sunscreen ingredient approved in the U.S. in more than 20 years. Cost to bring BEMT through FDA: About $18 million - Michael Scaturo says DSM spent roughly this amount on the FDA approval process. Expected U.S. shelf availability: By October at the latest - DSM expects BEMT-containing sunscreens to reach stores by this timeframe. Main UV protection types: UVA and UVB - BEMT protects against both, unlike many U.S. filters that mainly target UVB. Existing inorganic UV filters in the U.S.: 2 - AJ Aday identifies zinc oxide and titanium dioxide as the two inorganic filter classes allowed in the U.S. Broad-spectrum ingredient comparison: 1 other U.S.-allowed broad-spectrum filter - Avobenzone is noted as the only other U.S.-allowed UV filter with broad-spectrum absorption, though it requires stabilizers. Sunscreen ingredients flagged by FDA in 2019: About 12 chemicals - Scaturo references FDA action that moved several ingredients into a gray area requiring more data. Remaining widely used flagged ingredients: 4 - He says four of the previously questioned chemicals are still widely used in sunscreens.
Pivotal Quotes: "This fundamentally changes the landscape a bit." — AJ Aday: On the significance of the FDA approving BEMT after more than two decades. "What's great about BEMT is that it actually very efficiently absorbs both UVB and UVA rays, which would make it more of a broad spectrum filter." — AJ Aday: Explaining the ingredient’s key technical advantage over many current filters. "I think the main reason is that it's expensive to bring a new drug through the FDA because in the United States, sunscreen chemicals are considered over-the-counter drugs." — Michael Scaturo: Explaining why U.S. approval took so long compared with other countries.
Implications: BEMT could make U.S. sunscreens more effective, more elegant to wear, and easier to formulate. It also highlights how drug-style regulation and public mistrust can slow adoption of globally used ingredients.