Skin, Lip and Body Care

Sunscreen Ingredients Absorbed More than We Thought: Should You Be Worried?

+ CV Skinlabs Team

According to dermatologists, the sun is enemy number one when it comes to the skin’s health and appearance. Sunscreen helps, but recent research has shown that some of the ingredients in sunscreen aren’t as safe as we’d like them to be.

Here at CV Skinlabs, we’ve always recommended that you stick with zinc oxide when it comes to sunscreen, and the results of new research from the U.S. Food and Drug Administration (FDA) once again confirm that recommendation.

Researchers found that many ingredients included in today’s sunscreen formulations are absorbed through the skin into the body at much higher levels than previously believed. What does that mean for your health and your skin?

Studies Show Sunscreen Ingredients Absorbed More Than Allowed

On January 21, 2020, the FDA announced the results of its second sunscreen absorption study. The results from the first study were published in May 2019 and showed that the application of 4 commercially available sunscreens resulted in the systemic absorption of some sunscreen ingredients at levels higher than expected.

The FDA allows sunscreen manufacturers to bypass clinical studies on their products if those products are found not to expose people to higher-than-established levels of some potentially toxic ingredients.

The maximum level allowed of these ingredients in the blood is 0.5 ng/mL. In other words, after a person applies the sunscreen, less than 0.5 ng/mL of the ingredients in that sunscreen should absorb through the skin into the bloodstream.

As long as none of the ingredients show up in blood tests higher than this level, manufacturers don’t have to conduct clinical trials on their products to ensure that they’re safe for the public.

In that first 2019 study, the FDA found that in the 4 sunscreens tested, active ingredients including avobenzone, oxybenzone, octocrylene, and ecamsule absorbed at levels higher than those set by the FDA.

  • Avobenzone: 4.0 ng/mL
  • Oxybenzone: 209.6 ng/mL
  • Octocrylene: 2.9 ng/mL
  • Ecamsule: 1.5 ng/mL

Levels varied slightly depending on whether a lotion, spray, or cream was used.

Concentrations greater than the limit of 0.5 ng/mL were reached for all 4 products after 4 applications on one day. The researchers noted that these levels exceeded the threshold established by the FDA and that the absorption of the sunscreen ingredients “supports the need for further studies.”

Thus, the FDA’s second study. This time, researchers tested 6 sunscreen active ingredients from 4 commercially available sunscreen products on 48 healthy participants. Again, they found levels higher than those allowed by the FDA. Blood concentrations of all 6 active ingredients were greater than 0.5 ng/Ml, and this level was surpassed on day 1 after a single application.

  • Avobenzone: 7.1 ng/mL
  • Oxybenzone: 258.1 ng/mL
  • Octocrylene: 7.8 ng/mL
  • Homosalate: 23.1 ng/mL
  • Octisalate: 5.1 ng/mL
  • Octinoxate: 7.9 ng/mL

As before, the levels varied slightly depending on the form of delivery (lotion, spray, cream).

FDA Advises People to Continue Using Sunscreen

In response to the results, Janet Woodcock, M.D., director of the FDA’s Center for Drug Evaluation and Research, released a statement indicating that even though some sunscreen active ingredients are absorbed, that doesn’t mean the ingredients are unsafe. She did acknowledge that we need “further industry testing to determine the safety and effect of systemic exposure of sunscreen ingredients, especially with chronic use.”

The FDA has advised people to continue using sunscreen, as the benefits outweigh the risks, and meanwhile, they have requested additional information on the active ingredients to evaluate their status “in light of changed conditions,” including the fact that people use sunscreen much more today than they did a couple of decades ago.

Potential Dangers Linked with Sunscreen Ingredients

The FDA may not be ready to say that any of the ingredients listed above are unsafe, but other organizations have warned against using them. Here’s what we know so far:

  • Oxybenzone: The Centers for Disease Control and Prevention (CDC) has found that 97 percent of Americans have this ingredient circulating in their bodies. It’s classified as irritating to the eyes, and has a weak estrogenic effect, meaning that it may interfere with hormonal activity. It has been linked with altered birth weight in humans and low testosterone levels in teenage boys and is a frequent skin allergen.
  • Octinoxate: We don’t have enough studies on this yet to determine its safety. It also has hormone-like activity and was found in animal studies to interfere with thyroid function.
  • Octisalate: Often used to stabilize avobenzone, it easily penetrates the skin. We don’t have enough studies to determine its safety.
  • Octocrylene: Again, we don’t have enough studies on this to determine if it’s safe or not. It is linked to relatively high rates of skin allergies. It is also known to accumulate in the body.
  • Avobenzone: Though considered safer than oxybenzone, it can degrade when exposed to sunlight, increasing the presence of damaging free radicals in the skin.
  • Homosalate: We need more studies on this one, but we know it disrupts hormones like estrogen, androgen, and progesterone.

All of the above ingredients are known to penetrate the skin and sink into the bloodstream at varying levels. Since we know so little about their safety, it’s best to avoid them for now until the FDA finds out more.

Meanwhile, what to do about sunscreen protection?

How to Choose Your Safest Sunscreen

We continue to recommend zinc oxide and titanium dioxide as the safest active sunscreen ingredients. Studies show that very little absorbs through the skin, and neither has been linked with any hormone disruption, yet they provide broad-spectrum protection against damaging UV rays.

You can find these ingredients in so-called “mineral” sunscreens or simply look at the ingredient list to see what you’re getting. There is also some concern about inactive ingredients in sunscreens, including preservatives (which have been connected to increases in skin allergies), so try to find formulas that use few other ingredients and are made by conscientious companies.

To find the best product for you, check out EWG’s Guide to Sunscreens. You’ll find all the information you need there, and you can also check any products you already have to see how the EWG scores them in terms of safety.

Are you careful in your choice of sunscreen?


Sources
EWG’s 2019 Guide to Sunscreens. “EWG’s 2019 Guide to Safer Sunscreens.” EWG | Environmental Working Group. Accessed February 6, 2020. https://www.ewg.org/sunscreen/report/the-trouble-with-sunscreen-chemicals/.

FDA. “FDA Announces Results from Second Sunscreen Absorption Study.” U.S. Food and Drug Administration. Last modified January 21, 2020. https://www.fda.gov/news-events/fda-brief/fda-brief-fda-announces-results-second-sunscreen-absorption-study.

FDA. “FDA Announces Results from Second Sunscreen Absorption Study.” U.S. Food and Drug Administration. Last modified January 21, 2020. https://www.fda.gov/news-events/fda-brief/fda-brief-fda-announces-results-second-sunscreen-absorption-study.

Matta, Murali K., Jeffry Florian, Robbert Zusterzeel, Nageswara R. Pilli, Vikram Patel, Donna A. Volpe, Yang Yang, et al. “Effect of Sunscreen Application on Plasma Concentration of Sunscreen Active Ingredients.” JAMA 323, no. 3 (2020), 256. doi:10.1001/jama.2019.20747.

Matta, Murali K., Robbert Zusterzeel, Nageswara R. Pilli, Vikram Patel, Donna A. Volpe, Jeffry Florian, Luke Oh, et al. “Effect of Sunscreen Application Under Maximal Use Conditions on Plasma Concentration of Sunscreen Active Ingredients.” JAMA 321, no. 21 (2019), 2082. doi:10.1001/jama.2019.5586.

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