Sunscreen with Oxybenzone Dangerous to Corals
While V.I. National Park rangers ask visitors not to use sunscreen containing oxybenzone because it harms coral reefs, a study out this week makes clear the problems.
The researchers found that oxybenzone, a common UV-filtering compound that is found in high concentrations in the waters around the more popular coral reefs in Hawaii and the Caribbean, not only kills the coral, it causes DNA damage in adults.
The compound also deforms the DNA in larval stage coral, making it unlikely they can develop properly.
The highest concentrations of oxybenzone were found in reefs most popular with tourists.
“Coral reefs are the world's most productive marine ecosystems and support commercial and recreational fisheries and tourism,” said John Fauth, a University of Central Florida professor and contributor to the report.
“In addition, reefs protect coastlines from storm surge,” Fauth said in a Tuesday press release. “Worldwide, the total value of coral reefs is tremendous. And they are in danger.”
Ironically a sunscreen product that goes by the name of Reef Safe contains 4 percent oxybenzone, a description on the online retailer Amazon indicates.
The Professional Association of Diving Instructors, better known as PADI, lists 10 sunscreens on its website it considered safe. They are Aubrey Organics Natural Sunscreen Sensitive Skin/Children, SPF 30+, Badger Sunscreen Cream, Unscented SPF 30, UV Natural Sport Lip Sunscreen SPF 30+, Badger Broad Spectrum Sport Facestick SPF 35, ECO logical All Natural Sunscreen SPF 30+, Elemental Herbs Sport Sunscreen SPF 30+, Green Screen D Organic Sunscreen Original, SPF 35, BurnOut Ocean Tested Physical Sunscreen SPF 30, Raw Elements USA Eco Formula SPF 30 and All Terrain KidSport SPF 30.
On the National Park Service website, information about coral reefs indicates that while no sunscreen has been proven to be completely reef-friendly, those with titanium oxide or zinc oxide, which are natural mineral ingredients, have not been found harmful to corals.
Sunscreens sold for children or for those with sensitive skin may contain gentler compounds as the active ingredients, according to the website.
Greg Gunderson, who manages the Friends of V.I. National Park stores in Mongoose Junction and inside the park’s visitor center, said that while the stores are just now ordering merchandise for the winter season, the sunscreen’s impact on coral reefs will be a factor in what he orders.
“But this is not a new issue,” he said.
Executive director and researcher Craig Downs of the nonprofit scientific organization Haereticus Environmental Laboratory in Virginia led the team that evaluated the impact of sunscreen on reefs. The scientists collected samples from reefs in Hawaii, the U.S. Virgin Islands and Eilat, Israel, by diving into the water themselves. They wore no personal hygiene products during the dives.
"The use of oxybenzone-containing products needs to be seriously deliberated in islands and areas where coral reef conservation is a critical issue,” Downs said. “We have lost at least 80 percent of the coral reefs in the Caribbean. Any small effort to reduce oxybenzone pollution could mean that a coral reef survives a long, hot summer or that a degraded area recovers.”
“Everyone wants to build coral nurseries for reef restoration, but this will achieve little if the factors that originally killed off the reef remain or intensify in the environment," Downs said.
In laboratory experiments, the team exposed coral larvae and cells of adult corals to increasing concentrations of oxybenzone. The research team discovered that oxybenzone deforms coral larvae by trapping them in their own skeleton, making then unable to float with currents and disperse.
Oxybenzone also caused coral bleaching, which is a prime cause of coral mortality worldwide.
Corals bleach when they lose or expel the algae that normally live inside them, thus losing a valuable source of nutrition.
In addition, coral larvae exposed to increasing oxybenzone concentrations suffered more DNA damage.
Cells from seven species of corals were killed by oxybenzone at concentrations similar to those detected in ocean water samples. Three of the species that the researchers tested are currently listed as threatened under the U.S. Endangered Species Act.
To protect the reefs, Fauth suggested that people wear wetsuits or clothing called rash guards that covers up swimmers.
“If we could do it for a week at a time, people can certainly forgo it for a few hours to help protect these reefs for our children and their children to see,” Fauth said.