Review of Fate, Exposure & Effects of Sunscreen in Aquatic Environments & Implications for Sunscreen Usage and Human Health

The protective effects of sunscreen are well known, but the impacts on aquatic life are not. When sunscreen leaches into water from people swimming or through wastewater runoff, what risks do key active ingredients in sunscreens — like ultraviolet filters — pose to the environment?

In their August 4 National Academies of Sciences, Engineering, and Medicine report, "Review of Fate, Exposure, and Effects of Sunscreen in Aquatic Environments and Implications for Sunscreen Usage and Human Health" Exponent's Charles A. Menzie, Ph.D., principal scientist, and co-authors, examine 17 chemical and mineral UV filters used in the U.S. "to better understand the potential risk of UV filters on our already threatened aquatic environments, and the potential consequence to human health should sunscreen usage or composition be modified."

Dr. Menzie, chair of the NASEM Committee on Environmental Impact of Currently Marketed Sunscreens and Potential Human Impacts of Changes in Sunscreen Usage, and his committee colleagues offer a thorough review of the state of science on the sources and inputs, fate, exposure, and effects of UV filters in aquatic environments. The report was also the basis of a briefing to the Environmental Protection Agency and the public co-led by Dr. Menzie August 9.

Based on their review and examination of issues such as bioaccumulation and chemical harm, the authors recommend that EPA launch "an ecological risk assessment (ERA) for all currently marketed UV filters and any new ones that become available" to better understand their possible risks to and impact on aquatic ecosystems and human health. Because variability among filter concentrations and the sensitivity of exposed species make determining the environmental risk of UV filters complex, the authors advise the EPA assessment focus on a multitude of factors, including a broad range of species, interactions among UV filters, and environmental stressors, such as climate change.

From the publication: Restrictions on certain UV filters may have negative impacts on the use of sunscreen to prevent skin cancer, sunburn, and photoaging if they lead to reduced sunscreen usage.

This assessment is critical, the report states, not only to enhance our understanding of the risks UV filters pose to the environment but also to assess how potential changes to UV filter availability may affect sunscreen usage and human health.