Several countries have banned conventional sunscreens. Those who use these chemically active protective agents may face significant penalties. Governments have sound scientific grounds for these bans: the active ingredients octinoxate and oxybenzone act as chemical UV filters. However, they are also highly bioactive on corals, specifically causing severe degradation.
Tests conducted by a research group at the Università Politecnica delle Marche in Ancona, Italy, demonstrate that within 18 to 48 hours of exposure to such chemical-based sunscreens, substantial quantities of symbiotic algae and coral tissue were expelled. This occurred even at low concentrations (10 microliters per litre of seawater). After 96 hours, the corals were completely bleached, a process further accelerated by rising water temperatures.
Estimates suggest that 4,000 to 6,000 tonnes of sunscreen enter tropical reef regions annually via recreational swimmers.
The researchers warn that up to 10% of the world's coral reefs could be threatened by this pollution. Consequently, chemical-based sunscreens are increasingly being prohibited.
Mineral-based sunscreens offer an alternative. These typically form a physical barrier on the skin using titanium dioxide and zinc oxide filters to reflect solar radiation. While the ecological side-effects of these mineral formulations may not yet be fully understood, they are currently considered non-toxic to corals and marine fauna.
Jurisdictions with active bans (as of summer 2024):
- Aruba, Southern Caribbean, Netherlands. Ban on sunscreens containing oxybenzone in effect since 2020.
- Bonaire, Southern Caribbean, Netherlands. Ban on sunscreens containing oxybenzone and octinoxate in effect since 2021.
- Curaçao, Southern Caribbean, Netherlands. No statutory ban, but the local tourism authority strongly advises against purchasing ecologically harmful sunscreens locally.
- Hawaii, USA. General ban on non-mineral sunscreens in effect since 2022.
- Virgin Islands. Ban on sunscreens containing oxybenzone, octinoxate, and octocrylene in effect since 2020.
- Key West, Florida, USA. Ban on sunscreens containing octinoxate and oxybenzone in effect since 2021.
- Mexico, Tulum and Yucatán. Ban on sunscreens containing reef-damaging substances.
- Palau, Pacific. Ban on chemical sunscreens containing oxybenzone, octocrylene, parabens, and triclosan in effect since January 2020. Note: severe penalties apply, with fines of up to 10,000 USD for importing chemical sunscreens.
- Thailand. Ban on sunscreens containing oxybenzone, octinoxate, 4-methylbenzylidene camphor, or butylparaben in marine protected areas.
General recommendation: Investigations indicate that products marketed as "reef-safe" or "coral-friendly" in German retail outlets often still contain the chemical agents listed above. Chemical sunscreens should therefore be avoided when travelling to coastal destinations. In particular, prior to travelling to Palau, a rigorous check of ingredient lists is recommended to ensure formulations are strictly mineral-based.
Sources:
https://cordis.europa.eu/article/id/29485-sunscreen-serious-threat-to-corals-eu-study-finds/de
https://www.palaugov.pw/.../Sunscreen-Regulations-2020.pdf
