Polluting cosmetics: Study finds UV filters in sunscreen harm marine ecosystems

A study has found that UV filters in mineral-based sunscreens have a higher negative impact on corals than chemical-based alternatives. The Maldives-based study found that the filters damage marine life, can have genotoxic effects, and cause pigmentation and tissue loss in coral reefs.  

The researchers tested three sunscreens, all claiming to be “reef-safe” or “coral-friendly.” The two chemical-based sunscreens with organic UV filters caused mild or no adverse effects.  

However, mineral-based sunscreen with UV-filter zinc oxide (ZnO) demonstrated “severely negative effects.” High amounts of ZnO damage marine life, including mollusks, crustaceans, and algae, raising concerns due to increased levels of ZnO used in many cosmetic products. 

The researchers also point out that even organic UV filters can cause genotoxic reactions in corals.

Raising alarms

The study, published in Marine Pollution Bulletin, also compared organic and inorganic UV filters. The researchers found that organic UV filters from chemical sunscreens caused mild psychological changes, and the inorganic filter from the ZnO mineral sunscreen caused severe psychological stress across coral species.

ZnO was also linked with “severe stress and changes to water chemistry.” It caused pigmentation changes and rapid tissue loss in a four-day period. It was also found to harm the relationship between coral and the algae zooxanthellae, damaging cellular function and increasing oxidative stress. 

This lack of regulation is misleading consumers, the researchers argue. The organic filters had milder effects. One of the chemical-based sunscreens caused minimal changes even when tested at high concentrations and is, therefore, unlikely to pose a significant risk to reefs in open water conditions. 

However, organic UV filters such as BMBM may harm coral reefs when entering the aquatic environment. The researchers stress that prior studies have shown that exposure to organic UV filters may cause the same damage as the inorganic ones demonstrated in this study. 

The researchers call for further research and regulations to balance sun protection use without harming the marine environment. 

False claims

The study points out that the sunscreens tested had environmental claims, such as “reef-safe” and “coral-friendly,” although they cause mild to severe adverse effects.

The researchers argue that multiple products on store shelves lack adequate regulatory oversight, raising concerns about other widely used cosmetics.

“Without requiring a comprehensive ecological risk assessment, these labels are mostly unregulated, with existing standards focusing primarily on the absence of certain chemicals like oxybenzone and octinoxate,” they argue, claiming that the term “reef-safe” is often used as a marketing tool rather than for environmental safety. 

This lack of regulation also misleads consumers, guiding them to believe they are choosing the environmentally friendly option, although the products are still polluting various ecosystems.