Sunscreen chemical kills coral, study says
UCF prof: Swimmers should wear clothing
A common ingredient in sunscreen is highly toxic for coral even at incredibly low concentrations, according to findings set for release today by a scientific team that includes a UCF professor.
The chemical, called oxybenzone, blocks the sun’s harmful ultraviolet radiation but also acts in several ways to deform or kill a variety of corals, said John Fauth, ecology professor at the University of Central Florida.
“It’s really common and highly effective at blocking UV, but the issue we found is that it is very devastating to corals,” Fauth said. “Imagine somebody slathering on sunscreen and then jumping into the water. Now repeat that hundreds of thousands of times.”
Fauth said several types of sunscreen, while not always easy to find and purchase, do not use oxybenzone as an ingredient.
But he urged beachgoers and snorkelers to forgo sunscreen in favor of beach- and water-
friendly clothing, including the sort that surfers wear for sun protection.
“Put on a hat and some sensible clothes,” Fauth said.
The study examined coral in natural settings and in laboratory conditions. It found that harm was observed at levels as low as 62 parts of oxybenzone per trillion parts of water — a ratio equivalent to one drop of water in more than six Olympic swimming pools.
Several makers of sunscreens would not comment, saying they had not heard of the study.
Dan Knorr, president of Tropical Seas Inc., an Ormond Beach maker of Reef Safe sunscreen, said criticism of oxybenzone has been based so far on “junk science.”
He said his company has invested nearly $100,000 for laboratory testing that found his sunscreen products are not a threat to aquatic environments. Tropical Seas has focused on marketing its sunscreen as safe for corals.
A significant factor about Reef Safe, Knorr said, is that its oxybenzone is locked to other chemicals and unable to harm marine life.
Concerns about coral vulnerability to sunscreen chemicals emerged several years ago. More recently, a campaign started by the National Park Service in 2013 warns divers and snorkelers that “compounds in many sunscreens can harm the coral on our reefs.”
The park service explained that some sunscreen chemicals are able to “awaken coral viruses” that may ultimately bring on bleaching and death of corals.
“It adds up,” the park service stated. “Research tells us that 4,000 to 6,000 tons of sunscreen enters reef areas annually.”
The team of scientists from Virginia, Florida, the National Aquarium in Baltimore, the National Oceanic and Atmospheric Administration and Israel studied coral in several settings, including
“Research tells us that 4,000 to 6,000 tons of sunscreen enters reef areas annually.”
National Park Service
Florida and U.S. Virgin Islands. Each of the participants funded their part in the study.
Their report will highlight evidence that coral is harmed or killed by oxybenzone via at least three scenarios: The chemical stunts coral larvae, leaving them immobile; and it disrupts corals’ DNA and their developmental process.
Coral species in decline, including staghorn, boulder star and great star corals, were found to be particularly vulnerable to oxybenzone in sunscreen, according to the study.
Fauth said sunscreen chemical is yet another stressor for an ecosystem in decline globally. Earlier this month, NOAA declared a “global coral bleaching event” triggered by rising ocean temperatures.
Bleaching began in South Florida and Florida Keys in August and has expanded to the Caribbean, posing a threat to reefs of Puerto Rico and the U.S. Virgin Islands, according to the agency.
Fauth said the warming of oceans, particularly when triggered by the current El Niño climate event, is not something a single person can do much about.
But whether to use sunscreen in an area of coral reefs is a choice people can make, he said, and not using it may do more good than scientists can now document.
“There’s no reason to believe the ingredient wouldn’t cause damage to other marine organisms,” Fauth said.