PracticalDermatology

In the wake of a lively debate on the safety of sunscreen ingredients at the 2019 Cosmetic Surgery Forum (CSF) meeting in Nashville, a follow-up study showing that chemical sunscreen ingredients can be absorbed by the blood is re-sparking the controversy.

The new study, sponsored by the FDA, is a follow-up to a May 2019 report. The new report included a larger sample size and more sunscreen active ingredients and formulations, but both reached similar conclusions: sunscreen actives can travel to the bloodstream. That said, these findings, which appear in the Journal of the American Medical Association (JAMA), do not indicate that individuals should refrain from use of sunscreen, the authors of the study caution.

The randomized clinical trial with 48 healthy participants found maximum plasma concentrations for avobenzone were 7.1ng/mL for lotion, 3.5ng/mL for aerosol spray, 3.5 ng/mL for nonaerosol spray, and 3.3ng/mL for pump spray, following a single application of these products on day one and multiple applications through day four.

Lawrence Green, MD, a dermatologist in Rockville, MD, says that the new data do not change what he tells patients or what he said on the CSF podium. “I tell patients that just because a chemical is found in our bloodstream doesn’t mean it will have toxic effects,” he stresses. “The FDA has shown these ingredients are present in blood after application, but there is no evidence that they stay there for a prolonged period or are dangerous/toxic.”

Dr. Green also takes issue with the maximal use conditions required in the newly published study. “No one should be applying sunscreen on their bodies in the amount the FDA is using for their maximal use test, anyway,” he says.

But Edit Olasz Harken, MD, PhD, co-Founder of Harken Derm LLC and an Associate Professor of Dermatology Medical College of Wisconsin in Milwaukee, contends that such maximal use may be becoming the norm. “Parallel to skin cancer awareness increase, sunscreen usage has also increased, larger body surfaces are covered for many days, and, following guidelines, in large quantities with frequent re-application,” she says, echoing the comments she made at CSF.

IS Innovation the Answer?

One of the bigger issues in susncreen formulation is that FDA has not approved new chemical filters, Dr. Harken says. Sponsors and manufacturers have submitted applications for approval for eight chemical sunscreen filters between 2002 and 2009 and none has gotten a nod from the FDA.

Congress enacted the Sunscreen Innovation Act (SIA) in November 2014, which altered the process FDA uses to determine whether a sunscreen active ingredient is generally recognized as safe and effective (GRASE) and established time frames for agency review. In its new proposed guidelines published in February 2019, FDA recommended GRASE designation for two mineral filters and requested certain studies for the remaining chemical filters that are approved in the US.

As these new studies come, indicating that the chemicals are absorbed in the bloodstream, “dermatologists, like me, are worried that the public will hear ‘sunscreen is the new margarine’ or ‘sunscreens are not safe’ and will stop using them, thus creating a new epidemic of skin cancers,” Dr. Harken says. But “holding onto ‘old’ filters, such as oxybenzone, is not the right approach,” she says. “Money and effort by manufacturers and dermatologists should be spent on obtaining unbiased data on safety and formulation of new, safe, and efficacious sunscreen products.”

Are Coral Reefs in Jeopardy?

Drs. Green and Harken disagree over whether sunscreens are harming coral reefs.

“As far as coral reefs, all studies done—except one of them—show the concentrations of oxybenzone and octinoxate are nowhere near high enough levels in water to damage the coral reefs,” Dr. Green says. “And the one study that showed a slight, possible link had limited sampling of water and coral compared with the others. “

Both the state of Hawaii and the city of Key West, FL passed legislation to forbid oxybenzone and octinoxate starting in 2021, Dr. Harken points out. “There is no doubt that in the laboratory environment, oxybenzone and octinoxate (the two ingredients studied most extensively) have harmful effects on coral,” she says. “Questions arise about whether the concentration is high enough around the reefs to incite real harm and whether coral bleaching is rather attributable to rising sea temperatures and other environmental pollutants.”

Bottom Line

Omaha, NE-based dermatologist and CSF founder Joel Schlessinger, MD says that the new study should be taken seriously. “While it is likely rare that the average patient actually adheres to this particular schedule in real-life, the fact is that many people do reapply on a more frequent basis than every two hours, especially if they are in heavy sun and/or water activities,” says Dr. Schlessinger. “As dermatologists, we have to consider this study carefully, as well as the previous study that showed the potential of unintended absorption of standard sunscreen ingredients,” he says. “In my practice, I continue to encourage mineral-based sunscreens for my pediatric patients as well as pregnant women. Additionally, I encourage physical sunscreens for my patients who will be swimming in the ocean and potentially near coral reefs.”

All three doctors agree that a comprehensive sun protection program remains essential for everyone and involves clothing, sunglasses, hats, and sunscreens.

Save the Date:

Cosmetic Surgery Forum,
December 2-5, 2020,
JW Marriott Nashville, Nashville, TN.
To register, visit Cosmeticsurgeryforum.com.