Sunscreen is Damaging Our Coral Reefs – How Can We Protect Them AND Our Skin?

When you’re snorkeling or swimming during your vacation, the sunscreen that’s safeguarding your skin might also be endangering the vibrant coral reef and marine life below you. Discover how you can protect the marine destinations you visit, without putting your own health at risk.

For decades, we’ve heard about the importance of using sunscreen to protect ourselves against the sun’s harmful UV rays. So it should come as no surprise that the annual global sun care market is predicted to reach nearly $25 billion by 2024 – an increase of 68% from 2015.

There are two main types of sunscreen: physical (mineral) and chemical. Mineral sunscreens act as a physical barrier on top of your skin, reflecting the sun’s rays away from your body. Chemical sunscreens, on the other hand, contain synthetic compounds which absorb the UV light before it reaches your skin.

While lathering on sunscreen before hitting the beach may protect us from the dangers of sun exposure, it can have the opposite effect on life underwater.  It is estimated that 14,000 tons of sunscreen end up in the oceans each year. And this is not only from those of us who like to swim in the sea.  The sunscreen that you rinse down the drain when you shower can eventually find its way into the ocean. In addition, the convenient aerosol sprays can spread sunscreen particles across the sand. When the tide comes in, these chemicals can get washed out to sea.

Sunscreen has become part of our holiday rituals and daily skin routines, but many of these products contain numerous ingredients that can be damaging to marine life.  So damaging that some destinations including Palau, Hawaii, US Virgin Islands, Key West, and Bonaire are all in the process of banning toxic sunscreens.

How does sunscreen affect coral reefs?

But what exactly is all the fuss about? And why are some destinations taking such drastic measures? Is this day-to-day product really a threat to our reefs?

Unfortunately, research has found that some of the main chemicals used in sunscreens are harmful to corals and other marine life. One of the main culprits is Oxybenzone (Benzophenone-3), a chemical ingredient found in over 3,500 sun care products.

These chemicals can lead to coral bleaching, damage the DNA of corals, and increase abnormal growth and deformities. Sunscreen is likely just one more stressor that is making corals more susceptible to disease, such as the Stony Coral Tissue Loss Disease that is affecting reefs across the Caribbean Sea.

How does sunscreen cause coral bleaching? Corals are usually covered in zooxanthallae. These tiny creatures absorb light and use photosynthesis to create food for the coral. When corals become stressed due to increased water temperatures or pollution from chemicals found in sunscreen, they expel the zooxanthallae. These tiny creatures are a lifeline for the coral, and without them they lose the main food and oxygen source and also the wide array of colors that make coral so attractive. Bleached corals are more vulnerable to disease. Their growth is stunted and the damage will negatively impact the surrounding marine life. Although it is possible for some to recover, most bleached corals will starve to death.

But it’s not only chemical sunscreens that are harmful.  Mineral sunscreens sometimes contain nano-particles which are so small that they can be absorbed by marine life.  These minerals are toxic to many ocean species and can cause stress and ultimately death, even at low concentrations.

In addition to the harm caused to coral, sunscreen can decrease fertility in fish; accumulate in dolphins; damage the immune systems of sea urchins and deform their young; and impair photosynthesis in algae. While we’ve greatly expanded our knowledge around this subject in recent years, there is still much more research to be done to fully understand the impacts of sunscreen on coral reefs.

How to prevent sunscreen from harming coral reefs

Despite how worrying this all sounds, it is possible to enjoy the sun while refraining from using harmful products. Follow these tips to make sure you stay sun-safe and reef-safe:

Stay undercover

The easiest way to protect yourself is to stick to the shade, especially during the hottest hours of the day.

Cover up

T-shirts, hats and pants offer adequate protection.  Consider swimwear and clothing which contain UV protection in the material. And remember, if you’ll be wearing a wetsuit, there’s no need to apply sunscreen underneath!

Escape the midday sun

Enjoy the sun in the early morning or late afternoon to avoid the harshest rays between the hours of 10am and 2pm.

When buying sunscreen, think reef-safe

Luckily, you don’t have to give up sunscreen altogether. In recent years, you may have noticed more sunscreen bottles with labels indicating that they are ‘reef safe’ or ‘reef friendly.’  However, it’s important to note that these labels are not regulated and have no agreed specifications.

What is reef-safe sunscreen?

So you know that you want to buy sunscreen that is good for the environment, but what actually makes sunscreen reef-safe? When purchasing your next bottle of sunscreen, be sure to consider the following:

Don’t use aerosol sunscreens

Spray-on sunscreens create a chemical cloud that settles onto the sand. When the tide comes in these chemicals wash into the ocean.

Avoid sunscreens with harmful ingredients

When purchasing sunscreen be sure to check the ingredients list. Sunscreens that contain harmful chemicals such as Oxybenzone, Benzophenone-1, Benzophenone-8, OD-PABA, 4-Methylbenzylidene camphor, 3-Benzylidene camphor, Octinoxate, and Octocrylene.

Choose non-nano mineral sunscreens

Opt for mineral sunscreens that use ingredients such as zinc oxide or titanium dioxide. But remember that not all mineral sunscreens are reef-safe. In order to be reef-safe, the ingredients must be “non-nano,” or larger than 100 nanometer in size, as this makes it less likely that it will be absorbed by marine life.  Choose mineral products that indicate that the ingredients are non-nano, for example “non-nano zinc oxide”.

Look for credible reef-safe certifications

Don’t rely on general claims from the manufacturer that their product is reef-safe. Look for third-party certifications, such as the Protect Land + Sea Certification, that designate it as such.

Spread the word about the importance of reef-friendly sunscreen

In addition to changing your own behavior, you can drive consumer demand by advocating for more reef-safe sunscreen options and raising awareness. Educate others about the consequences of certain sunscreens and let them know how they too can keep themselves and the reef safe.