Sunscreen: Saving you while killing others

When you go to the beach, one of your first thoughts is that you have to protect yourself. You take out your sunscreen, put it all over your body, and then head into the ocean for a swim. However, what you don't realize is that while you're protecting your own skin and preventing it from being damaged, you're actually damaging something just below the surface of the water that isn’t visible straight away. It's home to all sorts of life and does wonders for our world, and it's something we need to protect. Can you guess what it is? If you guessed coral reefs, you would be correct! Coral reefs are damaged by the chemicals found in most sunscreens such as oxybenzone and octinoxate, and many people are unaware of what the chemicals are and what chemicals do to the coral. They don't realize that by simply taking a swim in the ocean to cool off or to have fun is actually harming and killing coral. They also don’t realize how important coral really is.

What gives the coral their vibrant color is zooxanthellae, a microscopic algae that covers the coral. Coral have a symbiotic relationship with the algae that lives in their tissue. The algae serves as the coral's food source, providing the coral nutrients when the algae performs photosynthesis, and the algae consumes waste products from the coral. The coral also provides the algae with a protected environment. However under stressful situations, the algae will leave the coral’s tissue, taking away its food source, and turn the coral white in a process known as bleaching. The algae leave for a variety of reasons, such as pollution, rising ocean temperatures, acidification, naturally occurring coral disease and overexposure to sunlight. Bleaching does not necessarily mean death for the coral, but it leaves the coral much more susceptible to coral diseases and increases the mortality rate. So how does sunscreen relate to the coral and its algae?
Many sunscreens contain the chemical oxybenzone that protects human skin from UV rays and damage. However the chemical has a significant impact on coral. A study from 2015 investigated oxybenzone's effects on Stylophora pistillata in its larval form (also known as planula), a certain kind of coral.When the planulae were exposed to the chemical, there was an increased rate of bleaching. This is because oxybenzone is both a phototoxicant and a genotoxicant- the effects of oxybenzone are increased after exposure to light and it damages the coral of DNA. They also found that it increased ossification in coral where the coral became encased in its own skeleton. The study also showed there were significant concentration levels of oxybenzone per liter in the waters of US Virgin Islands. 

   

                                                                            

         Coral reefs cover only 1% of the ocean’s floor yet are home to at least 25% of marine life with 4,000 species being able to live in one reef. The coral is also full of fish nurseries, and helps baby fish grow and mature as the coral gives them protection from predators and security in more shallow waters. From only 1 square kilometer, 35 tons of fish can be found. Coral reefs are essential because they provide food and shelter for fish as well as protect the coastline in natural disasters. However we have already killed 10% of coral reefs, with 60% of the remaining reefs at a high risk. And as of now, over 14,000 tons of sunscreen enter our oceans. Many people enter the ocean for a swim, washing all of their sunscreen off in the ocean and bringing the chemicals straight to the coral. What can also happen is the sunscreen (especially with the popular spray-on sunscreens) will settle into the sand and when the tide pulls the sand into the water it brings the sunscreen with it.

So what can be done about this? The first step is awareness, and learning to look at labels on sunscreen. There are plenty of reef-safe, mineral based sunscreens out there. Lists of sunscreens that are safe for reefs have been published by Haereticus Environmental Lab and Environmental Working Group. Sunscreens that contain titanium and zinc oxide and are mineral based are much safer. Many people are often put off by these kinds of sunscreens as they aren’t as visually appealing- they often leave the skin very white and don’t look as good as your traditional Banana Boat sunscreen. However, making small changes is how we solve the problem. By not purchasing or continuing to use these sunscreen, we lower the amount of sunscreen going into the ocean. There have been efforts on a larger scale to help the issue- On May 1, 2018 a bill was passed in Hawaii that banned certain harmful sunscreen chemicals that will take effect on January 1, 2019 as law. It targets sunscreen that contains oxybenzone and octinoxate, which are found in over 3,500 sunscreen items across the world. Resorts and tour companies have also been active in promoting the use of reef-safe sunscreens instead. There are currently coral nurseries set up in certain endangered areas to regrow coral and replant it as well.

Above is a diver working on a coral nursery, where living coral fragments are hung to allow them to grow again where they can then be transplanted to a new site. Below is a video (taken by me) of the coral nurseries I worked with and helped clean during my coral restoration trip. 

As a diver, I am interacting with coral constantly and have seen some amazing reefs. Seeing it up close and in person caused me to fall in love with it and strive to protect it. Watching fish swim around it, you see the underwater world for what it is- full of life and energy. The past summer I did a two week program in the Dutch Caribbean where I helped transplant coral, clean the coral nurseries, and clean beaches. It was an eye-opening experience that made me more aware of how small actions could have a larger impact. While the vibrant coral you find in Hawaii and the Virgin Islands doesn't seem to exist up at the New Jersey Shore, the sunscreen you use in New Jersey enters the same ocean as the Caribbean. Will wearing your favorite Neutrogena sunscreen to Ocean Grove kill the coral in Bonaire? Not directly, but the chemicals will still be entering the ocean and small doses can reach coral reefs. So even when you visit Cape Cod with your family or travel out to California, be aware of the sunscreen you are putting on your body- it is all entering the same ocean, and coral reefs need as much help as they can get. While I don't have the best photos, here are some photos/videos from my trip! (the first one I have shown to almost everyone, and was one of the coolest things I have ever experienced and the second one is a video of replanted Staghorn coral growing on bamboo structures)