The study, released Tuesday, was conducted in the U.S. Virgin Islands and Hawaii several years after a chance encounter between a group of researchers on one of the Caribbean beaches, Trunk Bay, and a vendor waiting for the day’s invasion of tourists. Just wait to see what they’d leave behind, he told the scientists – “a long oil slick.” His comment sparked the idea for the research.
Not only did the study determine that a tiny amount of sunscreen is all it takes to begin damaging the delicate corals — the equivalent of a drop of water in a half-dozen Olympic-sized swimming pools — it documented three different ways that the ingredient oxybenzone breaks the coral down, robbing it of life-giving nutrients and turning it ghostly white.
Research for the new study was conducted only on the two islands. But across the world each year, up to 14,000 tons of sunscreen lotions are discharged into coral reef, and much of it “contains between 1 and 10 percent oxybenzone,” the authors said. They estimate that places at least 10 percent of reefs at risk of high exposure, judging from how reefs are located in popular tourism areas.