A recent study, published in JAMA, showed that 4 active ingredients in sunscreen—avobenzone, oxybenzone, octocrylene, and ecamsule—may exceed the maximal threshold for systemic absorption in blood samples collected from 24 volunteers.1 According to the authors of this study, the findings support the need for more safety testing. However, they also emphasized that consumers should continue to use sunscreens.
The Dermatologist spoke with corresponding author David G. Strauss, MD, PhD, with the Division of Applied Regulatory Science, Office of Clinical Pharmacology, Office of Translational Sciences, Center for Drug Evaluation and Research at the FDA in Silver Spring, MD, about these findings.
The Dermatologist: Your study confirms the systemic absorption of 4 active sunscreen ingredients. What are the implications of this finding? What are the next steps for determining the safety of these ingredients?
Dr Strauss: The systemic absorption of sunscreen active ingredients supports the need for further studies to determine the clinical significance of these findings. The FDA has provided guidance for products that are absorbed, which includes systemic carcinogenicity and additional developmental and reproductive studies. There were prior studies that demonstrated absorption of some sunscreen ingredients.
You may also like...
Q&A: Rita Pichardo, MD, on Sunscreen and UV Protection Strategies
FDA Issues New Sunscreen Regulations
Currently, there are limited data on the health effects of sunscreen active ingredients. The FDA recently issued a proposed rule to update regulatory requirements for most sunscreen products available in the United States. As part of this rule, we are asking industry and other interested parties for additional safety data regarding the absorption of 12 of the 16 active sunscreen ingredients currently available.
The Dermatologist: Why has sunscreen not been subjected to standard drug safety testing?
Dr Strauss: While sunscreens are already available over the counter, the science has evolved over the years to be able to detect low levels of ingredients in the blood. It was unknown whether most active ingredients in sunscreens were absorbed.
The Dermatologist: As more data about systemic absorption of sunscreen products is collected, what should dermatologists consider when discussing sunscreen products with patients, especially in regard to safety concerns?
Dr Strauss: These results do not indicate that individuals should refrain from the use of sunscreen. While further data on sunscreens are developed, consumers should continue to use sunscreens with other sun protective measures. Broad spectrum sunscreens with SPF values of at least 15 remain a critical element of a skin-cancer prevention strategy that includes other sun protective behaviors, such as wearing protective clothing that adequately covers the arms, torso, and legs; wearing sunglasses and a hat that shades the whole head; and seeking shade whenever possible during periods of peak sunlight. In the FDA’s proposed rule, the FDA also proposed that two sunscreen ingredients (zinc oxide and titanium dioxide) be “generally recognized as safe and effective” and additional data is not required for those ingredients.
1. Matta MK, Zusterzeel R, Pilli NR, et al. Effect of sunscreen application under maximal use conditions on plasma concentration of sunscreen active ingredients: A randomized clinical trial [published online May 06, 2019]. JAMA. doi:10.1001/jama.2019.5586