October 20, 2015 — The sunscreen that snorkelers, beachgoers and children romping in the waves lather on for protection is killing coral and reefs around the globe. And a new study finds that a single drop in a small area is all it takes for the chemicals in the lotion to mount an attack.

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.

Yet beach crowds aren’t the only people who add to the demise of the coral reefs found just off shore. Athletes who slather sunscreen on before a run, mothers who coat their children before outdoor play and people trying to catch some rays in the park all come home and wash it off.

Cities such as Ocean City, Md., and Fort Lauderdale, Fla., have built sewer outfalls that jettison tainted wastewater away from public beaches, sending personal care products with a cocktail of chemicals into the ocean. On top of that, sewer overflows during heavy rains spew millions of tons of waste mixed with stormwater into rivers and streams. Like sunscreen lotions, products like birth-control pills contain chemicals that are endocrine disruptors and alter the way organisms grow. Those are among the main suspects in an investigation into why male fish such as bass are developing female organs.

Read the full story from The Washington Post