A recent JAMA study evaluated the systemic absorption (through the skin and into the body) of active ingredients in four sunscreens, and found at least one active ingredient in the four products entered the bloodstream.
The ingredient, avobenzone, measured a maximum plasma concentration of 4.0 ng/mL. The threshold for testing is .5 ng/mL.
The study’s takeaway is that the findings warrant further testing. And while “further study” might elicit alarm bells to some, for Bruce Brod, professor of dermatology at the Perelman School of Medicine, this doesn’t mean that it is an ingredient to avoid. In fact, quite the opposite.
“The important point of the study is that there haven’t been any safety red flags that emerged,” explains Brod.
Sunscreen is considered an over-the-counter drug—it is regulated by the FDA, and the FDA has been charged with updating the monograph on 12 commonly used sunscreens. The monograph determines how the ingredients should be used and formulated in products. Part of this update requires safety testing. The way sunscreen is used has changed over the years, and the FDA is just “catching up,” says Brod, to standard pre-market safety evaluations.
“The FDA is requiring normal testing on over-the-counter sunscreen to demonstrate safety. The reason it’s happening now is because the monograph—which is required for over-the-counter-drugs—has not been updated to reflect the changing way sunscreen is being applied.”
The two types of sun protection cream are chemical sunscreen with ingredients like avobenzone that absorb UV rays, and sunblock, with ingredients like titanium dioxide and zinc oxide, that reflect UV rays. A decade ago, the sunscreen market went through a period of public concern and confusion regarding micronized physical sun blockers. In 2009, testing of microsized titanium and zinc blockers found no penetrants in the bloodstream. Earlier this year, the FDA formally declared mineral sunscreen ingredients are safe, specifically zinc oxide and titanium dioxide. Testing on avobenzone and chemical sunscreen chemicals are following the same protocol.
“It’s good news that tech has evolved to micronize physical UV blockers,” says Brod. “Consumers want to have safe choices, and many find zinc and titanium sunblock to be ‘inelegant.’ Now consumers can choose sunblock that is not as chalky on the skin, or a chemical sunscreen, and know that both are safe.”
However, Brod has a clear message that echoes the FDA: Sunscreen shouldn’t be the only tool to protect against the sun. “This we know: Sunlight causes cancer. Sunscreen plays a role against something that causes cancer. Performing additional safety tests is never a negative thing; it doesn’t mean it’s unsafe.”
The best protection is to avoid the sun when possible, and wear sun protective clothing. Even 15 minutes of sun exposure on unprotected skin can result in a sunburn. The American Academy of Dermatology confirmed that 80% of the sun’s UV rays can penetrate the skin on a cloudy day. And a long-term study conducted in Australia confirmed that repeated exposure to the sun without sun protection results in an increase of wrinkles and tissue regeneration. Studies have repeatedly confirmed the damage UV rays have on the body, and clinical trials of sun protection are now catching up.
Source: University of Pennsylvania