Scientists think they know what killed coral reefs. It was us

This 2016 photo from the National Oceanic and Atmospheric Administration shows bleaching and some dead coral around Jarvis Island, part of the U.S. Pacific Remote Marine National Monument. Scientists found 95 percent of the coral is dead in what had been a lush and isolated tropical marine reserve. Bernardo Vargas-Angel | NOAA, via AP

The bleaching of the coral reefs? Apparently, it’s your fault, beachgoers.

The mysterious deaths of the beloved coral reefs is being blamed on sunscreen, The Guardian reports today. While we figured it had something to do with climate change, something most people shake their head over but about which we often don’t really think they can make a difference on as individuals, sunscreen hits close to home. We loved the ocean to death.

It’s the chemical Oxybenzone, which the scientists say has the same effect as gasoline.

The recent research builds on several years of work by teams in Italy, Spain, Israel and Iran, and found that even small doses of oxybenzone – about a drop in six-and-a-half Olympic swimming pools – damages coral. The researchers found concentrations 12 times that rate in popular waters off Hawaii and the US Virgin islands. Hawaii lawmakers are proposing a ban on the use of such sunscreen on the islands.

In the Caribbean, Downs said, the researchers noticed that bays popular with sunscreen-slathered tourists had dead and sterile coral, while those with little traffic were healthy. “In one there’s just nothing there, it’s a desolate wasteland,” he said. “Two bays over, at a $1,000-a-night resort, where very few people go, there’s lots of coral recruitment, lots of spiny sea urchins.”

The scientists argue that this difference shows that climate change alone is not responsible for coral die-offs, and that such cases add to evidence that pollutants created sterile, “zombie” reefs. Downs’ team has also found that oxybenzone has toxic effects on fish larvae and embryos.

Hundreds of sunscreen products, including Coppertone and Banana Boat, use the chemical. The Guardian says sunscreen companies, which oppose any ban on the chemical, have started labeling their products “reef friendly” but there’s no standard for what that means.

In the meantime scientists have recommended people at least stop using the spray-on sunscreen because most of it falls onto the sand.