The Untold Story of Sunscreen and Coral Reefs
©Nattu Adnan
Does your idea of the perfect vacation center around days spend at the beach, basking in the sun with a captivating book in hand? Or do you prefer a more active approach, engaging in activities like surfing, boarding, or snorkeling beneath the ocean's surface? Regardless of your beachside routine, it's likely that sunscreen plays a crucial role in your vacation.
For centuries, we have recognized the importance of shielding our skin from the harmful effects of UV rays. However, a relatively recent revelation has shed light on the significant damage that certain sunscreens can inflict upon marine life, particularly coral reefs. In this edition of GREENEXT Talks, we delve deeper into the truth about corals and sunscreen, uncovering the vital connections between our sunscreen choices and the well-being of these precious ecosystems.
Why are coral reefs important?
©Евгения Пивоварова
Coral reefs are incredibly rich in biodiversity, surpassing any other ecosystem on the planet.
Despite occupying less than 0.1% of the ocean floor, they support more than 25% of all marine fish species, as well as numerous other marine creatures. Moreover, coral reefs provide a wide range of vital ecosystem services, including a source of subsistence food, protection against flooding, and support for the fishing and tourism industries.
Coral reefs directly sustain the lives of over 500 million people worldwide, particularly those in impoverished nations who depend on them for daily subsistence.
A 2014 assessment published in the journal Global Environmental Change valued the social, cultural, and economic worth of coral reefs at a staggering $1 trillion. Additionally, a 2015 study conducted by WWF predicts that the loss of reef ecosystem services due to climate change could cost $500 billion or more annually by the year 2100.
Furthermore, coral reefs serve as crucial indicators of the overall health of global ecosystems. They act as an early warning system, providing insight into the potential impacts of climate change on less sensitive systems like river deltas. Once coral reefs reach their tipping point and begin to decline, the deterioration of other ecosystems may accelerate rapidly and become irreparable.
Coral reefs also play a significant role in carbon cycling and climate regulation. They absorb carbon dioxide from the atmosphere and store it in the form of calcium carbonate, the main component of coral skeletons. This process helps mitigate the impacts of climate change by reducing greenhouse gas levels and ocean acidification.
However, corals are facing an existential crisis due to climate change and a range of local threats and stressors. According to the Global Coral Reef Monitoring Network (GCRMN) in 2020, there has been a steady decrease in hard coral cover since 2010. Since 2010, the amount of algae on the world's coral reefs has increased by about 20 percent, mirroring the decrease in the amount of hard coral over this period. Scientists predict that all coral reefs will be considered “threatened” by 2050. In addition to problems like overfishing, pollution, and climate change, one threat may be coming directly off your skin—sunscreen!
©Qui Nguyen
The damage of sunscreens on corals
©National Oceanic and Atmospheric Administration
Every year, an astonishing amount of sunscreen, equivalent to over 6,000 tons, flows into reef areas in the United States, surpassing the weight of 50 blue whales. The researchers found that sunscreen chemicals, including oxybenzone and octinoxate, were detected in high concentrations in coastal waters, indicating their presence in wastewater effluents. These chemicals have been identified as harmful to coral reef ecosystems by causing bleaching in corals.
Coral bleaching is a complex process that goes beyond the loss of vibrant colors in corals, which can be impacted by a few factors including climate change and chemical pollution. The brilliance of coral is attributed to the presence of microscopic algae known as zooxanthellae. These algae reside within the coral and engage in a mutually beneficial relationship, supporting each other's survival. As the algae depart, the coral gradually fades, resembling a bleached appearance.
December 2014 (left) and February 2015 show coral bleaching in the Pacific waters around American Samoa ©XL Catlin Seaview Survey
Coral bleaching matters because once these corals die, reefs rarely come back. With few corals surviving, they struggle to reproduce, and entire reef ecosystems, on which people and wildlife depend, deteriorate. An alarming example of the devastating impact of coral bleaching occurred in 2005 when the United States experienced a significant loss of half its coral reefs in the Caribbean within a single year.
To safeguard these precious marine ecosystems, several locations have taken proactive measures by implementing bans on sunscreens containing oxybenzone and promoting the use of reef-friendly alternatives. Various regions and countries have taken action to protect their coral reefs by banning sunscreens containing harmful chemicals. For example, Hawaii, the U.S. Virgin Islands, the island nation of Palau, and Bonaire have implemented legislation prohibiting the sale and use of sunscreens containing oxybenzone and octinoxate.
How to protect your skin and the ocean?
The terminology used to describe sunscreens as "reef-safe" or "reef-friendly" can be ambiguous, making it challenging to determine the appropriate actions to protect coral reefs. To help you make informed decisions about the impact of sunscreen on reefs, here are our recommendations:
Wear sun protection clothing
Opt for clothing that is rated with UPF (Ultraviolet Protection Factor), as it significantly reduces the amount of sunscreen needed. This helps minimize the direct application of sunscreen on your skin. You can learn more about sun protection clothing and its benefits.
Avoid oxybenzone or octinoxate
Evidence suggests that oxybenzone and octinoxate are among the most harmful chemicals to coral reefs. It's always recommended to carefully read the product labels and ingredients list to ensure that the sunscreen you choose is free from oxybenzone and octinoxate.
Use rub-on lotion
Instead of using spray sunscreens that can easily land on the sand and wash into the ocean, choose a rub-on lotion. This application method reduces the risk of sunscreen particles reaching the marine environment.
Look for good water resistance
Select a sunscreen with good water resistance to ensure it stays on longer while you're in the water. Follow the application instructions regarding the recommended waiting time before entering the water to maximize the sunscreen's water resistance.
Seek Shade
Seeking shade not only helps protect you from the harmful effects of UV rays but also provides a cooler environment. The peak intensity of UV radiation occurs during midday when the sun is directly overhead. To ensure smart sun protection, it is advisable to seek shade between 11 a.m. and 3 p.m. when the atmosphere provides the least amount of natural protection. Staying under a sun shade will reduce the amount of UV radiation shining down on you significantly.
