AmbergrisCaye.com Home Forums The Cayes Ambergris Caye Don't use sunscreen before diving.

From this month's Undercurrent Magazine.

"Skip The Sunscreen While Diving
It can damage and even kill coral reefs, says a study in the journal Environmental Health Perspectives. Italian marine biologists have linked four UV-blocking chemicals in sunscreens to coral bleaching because they cause viral infections in the symbiotic algae that live inside reef-building coral. The viruses replicate until their algae hosts explode, infecting neighboring coral. The researchers estimate that 5,000 tons of sunscreen wash off people in oceans annually, and that up to 10 percent of coral reefs are threatened by sunscreen-induced bleaching."


I've always advised people not to use it before diving as it just washes off (yes, even the "waterproof" stuff), but I didn't realise it was positively harmful.

Thanks Pedro, that is insight on an issue that I wasn't aware was an issue. My bald head needs protection, I'll just start diving with a "do-rag".

Last time I went snorkeling was in the Yucatan, and I wore a long sleeve white shirt. It was really no problem in the water and was comfortable. Got it packed for the trip now. Had no idea of the problem with sun screens - don't like them anyway, but don't like burning either.
Read somewhere on here that Isla Bonita had the best do-rags on the planet. Will check that out in a couple of days when I get there.

Good suggestion! I had heard that the "all natural biodegradable" sunscreen (like Mexitan) doesn't harm the reefs. Anyone heard any differently?
Does Belize require BC vests for snorkeling tours?

eh, gunks up my wetsuit.

BC vests are not required, personal choice depending on ability in the water.

Thanks for the important info!

I heard they found a chemical in coral from the Great Barrier Reef that is a highly potent sunscreen - may be safe someday.