If you're one of the millions of beachgoers who slathers yourself in sunscreen before hitting the surf, here's an additional reason to feel personally responsible for the sixth mass extinction. Your sunscreen, my sunscreen, all of our goddamn sunscreen is contributing to the death of Earth's coral reefs. Did I mention we suck?
Climate change may be Public Enemy #1 when it comes to reef-building corals, but for years, scientists have warned that oxybenzone, an ultraviolet-absorbing compound found in practically every major brand of sunscreen, might also be doing damage.
Now, a study published in Archives of Environmental Contamination and Toxicology has confirmed our suspicions. Oxybenzone kills coral. It disrupts their growth, increases the rate of coral bleaching, damages DNA, and can even cause the larval form of coral (called planula) to become trapped in their own skeleton.
According to the new study, a minuscule amount of sunscreen — the equivalent of a single drop in six Olympic sized swimming pools — contains enough oxybenzone to begin disrupting coral growth.
Across the world, 14,000 tonnes of sunscreen lotions are discharged into coral reefs each year. And it isn't just beachgoers who are at fault. No matter where you live, your skincare products wash off in the shower and wind up in a local waterway. Eventually, some of that water reaches the ocean.
Airport Reef in American Samoa photographed in August 2015 (after the bleaching event). Approximately 70% of the corals here are dead. Image Credit: XL Catlin Seaview Survey
Coral reefs harbour a quarter of the ocean's biodiversity, spawn many of the fish we eat, and protect thousands of miles of coastline from storm surge. Two weeks ago, a report from the National Oceanic and Atmospheric Administration concluded that we're in the midst of a massive coral bleaching event, a phenomenon which occurs when high temperatures disrupt the symbiotic relationship between coral and its photosynthetic food source, a green alga called zooxanthellae.
This year's coral bleaching could impact a full 38% of coral reefs worldwide. If current trends continue of ocean warming and acidification continue, some marine scientists think reefs could disappear entirely within the next several decades. The fact that humans are making this human-caused problem even worse by tanning is just sad.
"The use of oxybenzone-containing products needs to be seriously deliberated in islands and areas where coral reef conservation is a critical issue," study co-author Craig Downs told The Washington Post. "We have lost at least 80 per cent 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."
Thankfully, there's a pretty straightforward solution here: stop wearing sunscreen that contains this nasty shit. Check the ingredients list on your sunscreen bottle. If you wear L'Oreal Paris, Banana Boat, or another major brand name, you'll probably find oxybenzone. Chuck that bottle in the garbage and replace it with one of these oxybenzone-free brands. If you don't like any of those, these ones are ecologically responsible as well, though you may have to do a bit of hunting to get them in Australia.
Climate change is a hard problem, the hardest one our species has ever faced. This isn't. Let's all do our part to solve it.
Top: A completely bleached coral photographed in Hawaii during the main islands' first ever mass bleaching event in late 2014. Image Credit: XL Catlin Seaview Survey