Although there is no general consensus amongst scientists, most sunscreens are suspected to harm coral reefs and other marine life. Harmful are not only the particles and/or chemicals that come off while swimming but also what travels through sewage systems when washed off in the shower. Also, as sunscreen chemicals are absorbed by our skin and excreted by urine, they end up in the ocean eventually through this route.
The damaging effect of chemical sunscreen (e.g. chemicals like oxybenzone) and in which concentrations it is harmful is disputed amongst scientists. Some research, also disputed by others, consider mineral sunscreens including zinc oxide or titanium dioxide that are “non-nano” in size, safe. Important to check the ‘’non-nano’’ of these products which explains the particle size. Smaller particles (‘nano’) can be ingested by the coral polyps and are still harmful.
Unfortunately there is no scientific consensus yet on this issue. Protecting yourself from the sun is important, especially in the tropics. If you want to protect marine life, the choice for good protective clothing and staying less in the sun is a far better idea than using a lot of sunscreen. Especially if you go swimming, diving, surfing, needless to say that good sun-protective clothing is better for you and for the environment.
If there is more research, we will update this page. You can also subscribe to our newsletter on the contact page.