An urgent investigation is needed into the environmental impact of sunscreen on marine ecosystems, according to a new report.

Sunscreen products contain chemical compounds known as pseudo-persistent pollutants, which block ultraviolet (UV) rays but lead to bleaching and deformity in coral, and reduced fertility in marine species.

The global sunscreen market is rapidly expanding, with sales predicted to reach $13.6bn by 2028. However, significant amounts of these products are being washed into the ocean. One study in the report estimates that if half of an applied sunscreen washes off, a single beach with 1,000 visitors could lead to 35kg entering the ocean in a single day.

Published in Marine Pollution Bulletin, the review examined over 110 studies on sunscreen, UV filters, and their ecological effects. It found that between 6,000-14,000 tonnes of UV filters are released each year, highlighting the urgent need for further research.

“Current research has only scratched the surface of understanding how these chemicals can affect marine life,” says Anneliese Hodge, the study’s lead author and PhD researcher at Plymouth Marine Laboratory and the University of Plymouth.

“What’s particularly concerning is that these compounds are considered ‘pseudo persistent pollutants’ due to their continuous introduction into marine environments. We really need to understand how these chemicals interact in the marine environment and if they have the potential to bioaccumulate within the food chain.”

UV filter contamination has been detected worldwide, from tourist-heavy coastlines to remote locations like Antarctica. These pollutants enter marine environments directly through swimming and indirectly via beach showers or towels used to dry sunscreen-covered skin.

Benzophenone, the most common UV filter compound, has been identified as bioaccumulative and toxic. Benzophenone-3, widely used in sunscreens and cosmetics, is currently being reviewed by the European Chemicals Agency for its potential role as a hormone disruptor.

Sunscreen pollution also extends beyond marine ecosystems. In agriculture, wastewater from treatment plants—containing UV filter residues—is sometimes used as recycled irrigation water, allowing these contaminants to reach crops and freshwater sources via runoff.

Traditional wastewater treatment processes, including ozonation (a chemical method that uses ozone gas to remove pollutants), have proven ineffective in fully neutralising the toxicity of UV filters.

“There are increasing amounts and varieties of sunscreens entering the environment, and contaminants occur in all possible combinations,” says Prof Awadhesh Jha, a senior author of the review and professor in genetic toxicology and ecotoxicology at the University of Plymouth.

To address this issue, the review calls for increased research across diverse geographic regions and more extensive testing of sunscreen’s effects on different stages of marine life. Scientists stress that understanding and mitigating the impact of sunscreen pollution is essential for protecting marine biodiversity.