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Sunscreen Toxicity and Legislative Update from AADVMX 2021

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Several sessions at AADVMX focused on the human and environmental effects of the UV filters used in sunscreens. A paper in epub status by Michelmore et. al provided an extensive review of the environmental data. Dr. Henry Lim of Henry Ford Health System in Detroit noted that this paper reviewed a total of 32 published studies until June 2020 and covered data on 14 different organic UV filters in seawater near coral reefs. They reported that all detected UV filters were found in the ng/L range, and nine papers that reported toxicological findings, all were in the ug/L to mg/L range. When a weighted risk analysis compared the reports and different UV filters, it reported that only oxybenzone and octinoxate were above the threshold for predicted risk. The analysis concluded that there wasn't enough evidence to suggest that coral is adversely impacted by environmental exposure to UV filters, and there needs to be high‐quality monitoring and toxicity studies.

Steven Wang, MD of Memorial Sloan-Kettering Cancer Center in Basking Ridge, New Jersey, reviewed recent studies and summarized the FDA-mandated (Maximal Use Trials (MUST) reported by Matta et al. 2020. These studies utilized a 75% body surface area application four times daily for seven days, with various sunscreen products containing up to six active ingredients (avobenzone, oxybenzone, octocrylene, homosalate, octisalate, and octinoxate). Blood levels of all UV filters were found in subjects far above the FDA threshold for waiving further toxicity studies (0.5ng/ml) and were detected in blood and skin-stripping samples up to 21 days after the application was completed. They reported that these short-term levels had no detectable clinical significance and that long-term studies of real-world use were needed to look for cumulative human toxicities.

Both speakers also commented on the paper by Suh et. al (2020), which reviewed 29 studies looking for endocrinopathy association for oxybenzone and octinoxate. This review found no adverse effect on male and female fertility, female reproductive hormone level, adiposity, fetal growth, child's neurodevelopment, and sexual maturation for oxybenzone. A possible association of oxybenzone level on thyroid hormone, testosterone level, kidney function, and pubertal timing has been reported and should be investigated to validate a true association and no reported effect on thyroid and reproductive hormone levels for octinoxate. Their conclusion was similar to the Mitchellmore review that there is not sufficient evidence at this time to support the causal relationship between the elevated systemic level of oxybenzone or octinoxate and adverse health outcomes.

To further evaluate these areas of concern, Dr. Lim reported that on Feb. 9, 2021, the National Academies of Science, Engineering, and Medicine formed a committee to study this topic, sponsored by the Environmental Protection Agency.

Finally, Dr. Lim noted that the long-awaited FDA Final Rule on Sunscreens was replaced with an administrative order as a result of clauses in The Coronavirus Aid, Relief, and Economic Security Act (CARES Act) of March 2020. The FDA is now required to issue a proposed administrative order by September 27, 2021 (18 months after the CARES Act). After a period of commentary, a final administrative order will be issued, and the industry would have one year to comply, but there will be incentives for innovation that will grant 18-month exclusivity for new filters brought to the U.S. market.

AAD VMX was a well-organized but condensed and compartmentalized version of what the annual AAD meetings have been. It was a necessary part of the Academy's response to the pandemic. Virtual presentations and discussions will no doubt be part of the future going forward, and better platforms will allow better and more dynamic future meetings and perhaps some sort of hybrid with regional in-person events

Collage by Diana Connolly / UnitoneVector / petovarga / Getty

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