Sunscreen: Yet another threat to diminishing coral reefs

By: Ashley Gustafson

coral-reef-wallpapers-18The idea of sunscreen being harmful or even a bad thing is an irrational concept in a modern world where putting on sunscreen could be considered an act of survival. Sunscreen allows most of us the ability to spend hours in the sun (with reapplication and proper SPF of course) without the immediate threat of sun burn and the long term effects like skin cancer. By no means in sunscreen the cure-all or perfect UV protectant but it is proven to drastically limit ones chances of contracting a sun sickness of any sort. Therefore, sunscreen has a good, even heroic, reputation. It has become a habitual part of the day, as in if you are planning on being outdoors, you put on some degree of sunscreen. That is why when the latest news of sunscreen harming coral reefs came out; it has been such a big deal. Some studies report that even just one drop of residual sunscreen off a person’s body into the ocean could be detrimental to coral reefs.

While the news about the harmful effects of certain chemical runoff in the ocean has been prevalent for decades, this new study about the chemicals in sunscreen is frightening. This study states that just one drop of sunscreen has the potential to damage fragile coral reef systems around the globe. With that being said, it is important to note that coral reefs are in a critical state of decline, and that many (maybe even the majority) are currently in tremendously fragile states obviously leaving them vulnerable to this volatile runoff. Recently the National Oceanic and Atmospheric Administration (NOAA) released alarming news that the third massive global coral bleaching event in history is underway. On top of this current decline, yearly estimates of 14,000 tons of sunscreen lotion end up in the waters of coral reefs around the world and could be adding to the demise of coral reefs worldwide.

Dangerous Chemicals and coral

One ingredient that is found in many sunscreens, cosmetics, and hygienic products and that is a major problem for reefs is oxybenzone. Oxybenzone seeps the coral of its nutrients and causes bleaching, or the exodus of zooxanthellae causing the coral to become white and barren. On top of killing coral through bleaching events oxybenzone also has the potential to damage coral DNA in adults which can cause deformities in young coral DNA during the larval stage causing complications in development . These cellular level changes in coral can prevent coral reproduction all together. Oxybenzone is sadly found in more than 3,500 sunscreen products around the globe most likely including ones in your cabinet at home. Oxybenzone is found in some of the most popular sunscreen brands including Coppertone, L’Oreal, and Banana Boat. Sunscreen runoff has been recorded in popular tourist destinations like the U.S. Virgin Islands and Hawaii where sunscreen runoff from human bodies in the water is plentiful. A solution to this problem could be the limitations of sunscreens containing oxybenzone in waters that house coral reef systems. Craig Downs , co-author of the new study, states, “The use of oxybenzone-containing products needs to be seriously deliberated in islands and areas where coral reef conservation is a critical issue. We have lost at least 80 percent 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.”


As I mentioned previously, places that are seeing the most damage to coral reefs due to sunscreen are tourist destinations that rely heavily on tourism and their natural waters to attract visitors. To help, local businesses have started banning harmful sunscreens that contain chemicals like oxybenzone. In Akumal, Mexico they have put limitations on visitors who choose to wear sunscreen, restricting them to explore only certain areas of their coral reefs. While it is important to these destinations to save coral reefs from an economic stand point, coral reefs are also important biodiversity hot spots. They are so much more than beauty; they are complicated and diverse ecosystems that support countless numbers of organisms.

Now it may seem as though the only threat is humans wearing sunscreen and then swimming in the ocean but that is not the case. Another threat and possibility is that anytime anyone wears sunscreen it could end up in waterways which lead to the ocean. This is similar to washing harmful chemicals and cleaners down drains that end up in sewage and then can end up in the water. It is something that very few of us consider in our daily lives but those chemicals have to go somewhere and sadly they can end up harming coral reefs. According to John Fauth, a study’s co-author and an associate professor of biology at the University of Central Florida, “The most direct evidence [of damage] we have is from beaches with a large amount of people in the water. But another way is through the wastewater streams. People come inside and step into the shower. People forget it goes somewhere.”



Now these are bigger picture problems that can be very disheartening to think about. One person may not be able to change the whole outcome of chemical runoff into the ocean, but there are little things as one person you can do in your daily life to help aid in the damaging effects that chemical runoff is causing on coral reefs. Just by being conscious of how much harmful waste you contribute is a step in the right direction. By limiting waste as individuals we can hope that as a whole the effects will be minimized as well. Also, try using “coral safe” chemicals that are less harmful to coral. For sunscreens this means they are made with titanium oxide or zinc oxides which are natural mineral ingredients. Also, you can try to wear sun resistant clothing instead of sunscreen. This can include just wearing a hat and a shirt with SPF or wearing a rash guard or wet suit in the water. Cosmetic and hygienic problems also can contain harmful chemicals, and skipping them all together when you are planning on entering the ocean would help aid further coral reef damage.

On another note, this is also an important reminder for reef keepers and coral enthusiasts to keep their hands clean and rinsed when handling their coral or placing their hands in the water where their coral is kept. As I mentioned earlier, Oxybenzone isn’t found in sunscreen alone and since it is so toxic in such minor amounts, it is important to be aware of the potential harm it can have on your corals. It is used not only as a photoprotective agent (sunscreen) but also as a photostabilizer in many products like fragrances, hair spray, body lotions, cosmetics, and even nail polish. If you are uncertain what contribution you may have to your coral, wearing gloves is a great solution. Not only will it minimize the possibility of harmful chemicals coming in contact with your corals, but it also a protectant for your hands from coral.

Overall, sunscreen and sun protection are still very important aspects of spending time in the sun. My hope is this new study will bring a greater awareness of the harmful side effects of toxic chemicals in sunscreen on coral reefs as well as alert the masses to alternative sun protection besides relying on sun lotions and other sunscreen products. Coral reefs are beautiful and critical ecosystems in many parts of the world’s oceans. Protect your skin but remember to help protect coral reefs too and choose “coral safe” sun protection!



How Sunscreen May Be Destroying Coral Reefs