4 things to know about the newly approved sunscreen ingredient : NPR

For the first time in nearly 30 years, the Food and Drug Administration has approved a new chemical UV filter for sunscreens in the U.S., a development welcomed by many dermatologists.

“This is a very big deal,” notes Dr. Heather Rogers, a Seattle-based dermatologist and a fellow of the American Academy of Dermatology.

The newly approved ingredient, bemotrizinol, offers several benefits over the chemical sunscreen components previously available in the U.S., according to Rogers.

“It ticks every box we’ve been waiting for as dermatologists and consumers,” she asserts.

Here’s what you need to know about this new ingredient and the potential for improved sunscreens in the U.S.

1. It blocks both UVA and UVB rays

Rogers emphasizes the importance of using broad-spectrum sunscreens that protect against both UVA rays, which cause premature aging and wrinkles, and UVB rays, which lead to sunburns. Both types can contribute to skin cancer.

She notes that while sunscreens in the U.S. are effective against UVB rays, the chemical UV filters available until now have not been as effective at blocking UVA rays.

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Most chemical sunscreens in the U.S. depend on avobenzone for UVA protection, says Kelly Dobos, a cosmetic chemist at the University of Cincinnati.

However, avobenzone isn’t photo-stable, meaning its effectiveness diminishes quickly when exposed to sunlight. Its breakdown can release molecules that irritate the skin, according to Alexa Friedman, a senior scientist with the Environmental Working Group (EWG).

In contrast, bemotrizinol provides protection against both UVA and UVB rays by itself and is photo-stable, meaning it degrades more slowly and offers longer-lasting protection, says Rogers.

“So if you go a little longer than two hours to reapply your sunscreen, there will be more protection left,” Rogers says. However, she says you should still reapply sunscreen every two hours.

2. It’s long been used in other countries 

Bemotrizinol has been a staple in European and Asian sunscreens for decades, but it took 20 years for FDA approval in the U.S.

This delay is due to sunscreens being regulated as over-the-counter drugs in the U.S., requiring rigorous testing for safety and efficacy, unlike their classification as cosmetics in Europe.

“It’s really expensive and time-consuming,” Dobos explains. The company DSM-Firmenich invested at least $18 million over two decades to gain FDA approval for bemotrizinol.

3. It has a well-documented safety profile

Friedman of EWG points out that bemotrizinol has more safety data supporting it than any other chemical sunscreen ingredient currently approved in the U.S.

“This ingredient is exciting because we have that data to support its safety,” Friedman says.

Animal studies have shown bemotrizinol does not pose reproductive harm, and human clinical trials indicate it does not irritate the skin, even with repeated use, Friedman adds.

Moreover, due to its larger molecular size, bemotrizinol is not easily absorbed by the skin into the bloodstream, she notes.

This is significant because other chemical sunscreen UV filters in the U.S. have been found in the bloodstream, prompting demands for more safety data and causing a backlash on social media, fueled by misinformation. Rogers expresses concern about this trend as skin cancer is the most prevalent form of cancer.

“We just need to have sunscreen that people will use, that they’ll trust,” Rogers says. “And this ingredient is going to allow that to happen. And that is very exciting.”

And bemotrizinol is also considered to be non-irritating, Friedman says. That should be welcome news to people who’ve been put off by chemical sunscreens in the past.

4. It could lead to sunscreens that look better on you

Until now, Rogers says, the only sunscreen ingredient available in the U.S. that offered the aforementioned advantages of bemotrizinol – photo stable, non-irritating, minimally absorbed into the skin and with good broad spectrum protection against both UVA and UVB rays – was zinc oxide.

Both zinc oxide and titanium dioxide are mineral UV filters. Both chemical sunscreens and mineral sunscreens work by absorbing UV rays from the sun. Mineral sunscreens also reflect some UV rays. The bigger difference is that mineral sunscreens sit on the surface of the skin, while chemical sunscreens get absorbed into the skin, Rogers says.

Mineral sunscreens, however, often leave a white residue on the skin, which can be unappealing, especially for people of color, making them appear pale or ashy, says Rogers.

Bemotrizinol, however, is transparent on the skin. It protects against UVA and UVB rays without needing to be combined with many other chemical filters and stabilizers, Dobos explains. This should result in more cosmetically appealing, less greasy sunscreen options soon.

“I think it’s a real win for public health,” Dobos says. “If we can make a sunscreen that consumers like to use and want to use and apply in the proper amounts, I think that’s something that’s really going to be a win for consumers.”

DSM-Firmenich holds exclusive rights to market bemotrizinol in the U.S. for 18 months. It will be marketed as Parsol Shield, with American store shelves expected to stock products featuring this ingredient by September.