A guide to reef-safe sunblock

Suffering from sunburn is no fun. The blisters, the pain, and the damage to the skin itself are definitely best avoided. Over the last 30 years, the amount of UV rays reaching the earth’s surface has dramatically increased, especially if you live farther from the equator. That means the need for sunblock to protect your skin is more important than ever.

However, while trying to solve one problem, we may have created another by using some ingredients in sunblock that can cause major damage to marine life by starving coral reefs, creating disorders in wildlife, and even harming humans. But some sunblocks are worse offenders than others.

In this article, we will help you learn how to avoid sunblocks that contain harmful ingredients and provide tips to easily identify reef-safe and human-safe sunblock ingredients. We will also drop a a few recommendations for you to check out.

The impact of sunblock on coral reefs

Unfortunately, some of the ingredients in sunblock that are supposed to keep our skin safe are extremely harmful to coral reefs and other marine life.

Chemicals like Oxybenzone (Benzophenone-3) which is common in most sunblock brands, can cause a number of problems to the coral reefs, including mutating DNA, causing deformities, and sometimes causing them to die of starvation due to coral bleaching.

Bleaching occurs when chemical pollution from sunblock ingredients causes coral reefs to expel the algae that are supposed to cover their surface. This algae, called Zooxanthellae help the coral reef get its food from light through photosynthesis. They also give most of the coral the bright colors that they are known for. So when the coral reef loses the algae, they unfortunately starve and turn white.

Sunscreen and marine wildlife

Marine wildlife also suffer from additives in sunblock, such as nano-particles, which can cause them to become immunocompromised. This can be detrimental to the health of animals like dolphins and whales. When marine life is immunocompromised it means they are unable to fight infections leaving them susceptible to disease.

Even sea urchins, who have an amazing immune system are not safe from chemicals in sunblock. Oxybenzone can cause males to develop female attributes, and females to produce fewer eggs, which then impacts fertility overall.

These chemicals find their way to the large bodies of water mostly by being washed off of people who are swimming in the water and through shower drains which contribute to about 14,000 tons of sunblock products reaching the coral reefs each year.

The problems that these chemicals cause, not just for the coral reef, but for marine life by extension, might make you want to quit using sunblock altogether for the benefit of the environment. But it’s very important that your skin is protected. Luckily, companies have been working hard to develop sunblocks that will protect your skin without ruining the environment.

What is reef-safe sunblock?

The major difference to note between reef-safe sunblock and other sunblocks that claim to be safe for use, is that reef-safe sunblock is safe for both human and marine life. Many others only claim to be safe for human use, to hide the fact that they contain chemicals that harm coral reefs and other marine wildlife. Reef-safe sunblock on the other hand, contains chemicals that are safe for both humans and the reefs, leaving out those that impact marine life negatively.

Unfortunately, the regulations around what can be labeled reef-safe and what cannot are still undefined. No matter how ‘safe’ the label claims the to be, if it contains any of the ingredients we'll touch on below, it isn't.

True reef-safe sunblock will instead contain natural ingredients like zinc oxide and titanium dioxide, which are both mineral-based and great at physically blocking out UV rays from the sun, making them less harmful to marine life. That said, although these minerals are technically safe, if they are nano-sized than they can be toxic. So look for non-nano sized zinc oxide and titanium dioxide, which may be listed as micro-sized.

What ingredients to avoid

There are ten primary ingredients that are harmful to marine life which you need to avoid when buying reef-safe sunblock. Each one is individually harmful and does not need to be in combination with any other one to cause major problems. So, aim to always avoid all the following ingredients:

• Oxybenzone (Benzophenone-3) is a chemical compound that is not naturally occurring in marine environments, and is therefore toxic. This is the main ingredient that is responsible for coral bleaching.

• Octinoxate, along with Oxybenzone, is banned in sunblock products in many countries including Hawaii and The US Virgin Islands, for the damage it causes to the endocrine and reproductive functions of marine wildlife. That said, it’s not banned everywhere so always check the ingredient label.

• Octocrylene is harmful not only to marine life but to humans as well. For the coral reef, it can impact its ability to metabolize food. In humans, it can be absorbed through the skin and cause reactions that can lead to serious problems like heart failure.

• Homosalate is commonly used in sunblock that contains SPF, but it can also impact our hormone function and is linked to increased risk of skin cancer.

• 4-methylbenzylidene camphor, also known as Enzacamene, is another common ingredient in sunscreen but it can negatively impact the human reproductive system. It is also a main contributor to coral bleaching.

• Aminobenzoic Acid or Para-Aminobenzoic Acid (PABA) is safe for human use. However, the Haereticus Environmental Laboratory (HEL) recognizes the harmful effects the compound has on coral reefs.

• Parabens including methylparaben, propylparaben, and butylparaben, are preservatives used in pharmaceutical products including sunblock, to help them last longer on the shelves. However also kill marine microbes that are vital to marine life, and have been linked to breast cancer.

• Triclosan or TCS has been banned from use in medicated soaps by the FDA due to its links to cancer and endocrine diseases. It also impairs the reproductive development of fish.

• Any nanoparticles or “nano-sized” zinc or titanium, including the usually safe zinc oxide and titanium dioxide, could be harmful to the coral reef as well. Regardless of what the label says, a good test for whether a product contains micro or nano-sized zinc is to check how it appears on your skin, If it becomes transparent immediately after you put it in then it contains nanoparticles. If it remains white and sits on top of the skin then it contains microparticles, which means it’s reef-safe.

• Other forms of microplastic, such as “exfoliating beads” are also harmful to marine life. Not only to reefs, but also to marine wildlife like dolphins, fish, whales, and smaller life forms that may swallow them.

Best reef-safe sunblocks

The best sunblocks are those which do not contain any of the ingredients listed above, but that still provide adequate protection from the sun. Here are a few of our favorites!

1. Stream2Sea Sport Sunscreen has non-nano, titanium dioxide as its main ingredient, as well as coconut oil, tulsi leaf, seaweed, aloe, and green tea to make it skin-friendly and reef-safe as well.

2. Supergoop! Mineral Sheer Screen is part of the Supergoop brand of products that include sunblocks and lip balms that are made to protect from the sun and protect the ocean. It contains Zinc oxide and is safe for frequent use.

3. Suntegrity Skincare Natural Mineral Body Sunscreen contains SP50 mineral powders alongside aloe, cucumber extract, and hyaluronic acid, but none of the harmful ingredients listed above. This makes it a great profile for reef-safe sunblock.

Keep our reefs safe with reef-safe sunblock

The lack of regulation around reef-safe sunblock can make shopping consciously a struggle. Just because the label says the sunscreen is “safe” doesn’t mean that it is, and the industry experiences a lot of greenwashing as a result. That’s why it’s important to keep this list handy so you can identify the harmful ingredients before purchasing your sunscreen, and continue to keep our reefs safe!