Reef Safe Sunscreens

What’s the difference between suncream, sunscreen and sunblock?

Despite common misconception, there is basically no difference:

Suncreams and sunscreens are effectively synonyms unless you want to be picky about what you count as a ‘cream’. They act as a chemical barrier, filtering out ultraviolet light using chemical compounds. They often contain ingredients like oxybenzone or avobenzone. These compounds absorb UV radiation and convert it into a small amount of heat, which is then released from the skin

Sunblock is usually used to refer to mineral-based suncreams, on the basis that they works as a physical barrier, scattering the sun’s rays. In reality, though, they also they also absorb UV like chemical sunscreens. They typically contains minerals like zinc oxide or titanium dioxide.

Ultimately though, these terms are often used interchangeably, and personally I just called them all sunscreens. In terms of effectiveness, neither chemical or mineral-based options have a real advantage. If you’re interested in the science behind each of them, take a look at this article: https://labmuffin.com/how-do-sunscreens-work-the-science-with-video/

Sunscreen ingredients to avoid

Unfortunately, a lot of sunscreens are damaging to reefs. The ingredients oxybenzone (Benzophenone-3), octinoxate (Octyl methoxycinnamate) and octocrylene cause bleaching, can damage the DNA of coral, and can disrupt the endocrine (hormone) systems of fish.

Other ingredients to avoid are:

Para-aminobenzoic acid (PABA) – less common since it was discovered to be an allergen and irritant to some people, and harmful to a lot of marine life
Enzacamene (4-Methylbenzylidene camphor) – this hasn’t been studied much in terms of its damage to ocean life, but is believed to be an endocrine disruptor in people, and this may also carry over to other animals
Octisalate – potentially less harmful than chemicals like octinoxate, but still not considered reef safe
Homosalate – this again hasn’t been extensively researched, but is a known endocrine disruptor, and there concerns about its impact
Avobenzone – this is not very photostable, meaning it can break down into harmful chemicals like free radicals when exposed to sunlight, and it may also be a contributor to coral bleaching and endocrine disruption in marine animals
Nanoparticles (e.g. nano zinc oxide or nano titanium oxide) – research around these is more mixed, and several studies have not found any toxic effects, but others indicate they might harm phytoplankton (a critical part of marine ecosystems) by causing oxidative stress after exposure to sunlight

Safe sunscreen ingredients

Ideally, use mineral-based sunscreens (as opposed to chemical-based), with things like zinc oxide and titanium dioxide in a non-nano form. If it doesn’t specify that they are micro or non-nano, they probably aren’t; although nano-mineral sunscreens are still preferable to chemical ones.

There are also some newer chemical UV filters that are more photostable and hopefully less harmful though, like Tinosorb S (Bis-Ethylhexyloxyphenol Methoxyphenyl Triazine), Tinosorb M (Methylene Bis-Benzotriazolyl Tetramethylbutylphenol), Methylene Blue (an antioxidant previously used as a medicine and laboratory dye), but these aren’t as widely available.

Stick to these options if you can, but if not, oxybenzone, octinoxate and octocrylene, and probably PABA, are the main ingredients to avoid. The others haven’t been researched as extensively and some, like octisalate, may be less harmful. However, that doesn’t mean that they aren’t doing damage, and this lack of research means they could actually be just as bad – or potentially even worse.

Unfortunately, many people dislike completely reef-safe mineral-based sunscreens, because they generally have a thicker consistency that doesn’t rub in as well and can leave a white cast, and tend to be more expensive. Having said that, there are good options out there that minimise these issues, which are linked below.

Recommended reef safe sunscreens

Some good reef-safe sunscreens include:

Best All-Round Sunscreen: Hawaiian Tropic Mineral Skin Milk
Hawaiian Tropic is not generally known for being a reef-safe brand, but their mineral sun lotion has surprisingly few damaging ingredients, favouring zinc oxide over more harmful alternatives. It doesn’t specify if this is in nanoparticle form, so it likely is, but it’s effective and doesn’t leave a white cast once it’s rubbed in. It also smells GREAT, and is apparently a good base for foundation.
Available at: https://amzn.eu/d/1Xzo1oA

Best Non-Nano Sunscreen: Odylique sunscreen
This comes in both a plastic tube or a glass pot, and I’d recommend the latter, both because it’s more eco-friendly, and the tube can be a bit hard to squeeze suncream out of. Since it doesn’t use nanoparticles, it is thicker in consistency than alternatives, but safer for marine life and it does a good job of avoiding a white residue on the skin.
Available at: https://odylique.co.uk/natural-sun-screen.html?ref=duszyd4a1lzt

Best Non-Nano Alternative: Organii Sun Milk Cream with SPF 50 125 ml
Still a bit thicker than traditional sunscreens, but with a minimal white cast that goes away once rubbed in well. It’s also great for sensitive skin, with lots of natural ingredients.
Available at: https://amzn.eu/d/dSGvzNi

Best Sunscreen for Oily and Combination Skin: Australian Gold Tinted Mineral Sunscreen
The tint in this sunscream helps to avoid a white cast, particular for people with darker skin tones, since it comes in different shades. It’s also great for oily or combination skin, although some people with dryer skin have found that it aggravates that a bit.
Lighter shade: https://amzn.eu/d/guxVa4t
Darker shade: https://amzn.eu/d/8r1iNxt

Best Sunscreen for Dry Skin: IsNtree Hyaluronic Acid Natural Sun Cream SPF50+
Perfect if you have drier skin, this mineral sunscreen rubs in well to avoid leaving a white cast. There aren’t as many reviews on UK Amazon and a couple of poorer reviews seem to have dragged the ratings down, but on Amazon in other countries and other websites people seem very impressed with how well it blends in, and people with oily skin have also reported very good results.
Available at: https://amzn.eu/d/cR61HnA

Best Sunscreen for Dark Skin: Black Girl Sunscreen
With standard, matt, hybrid and child specific options, these mineral sunscreens were formulated by and for people with darker skin tones to avoid a white cast.
Available at: https://www.naturalisticproducts.co.uk/collections/black-girl-sunscreen

Best Face Sunscreen: CeraVe Moisturizing Mineral Sunscreen Face Sheer Tint
The tint in this does a great job at preventing any white residue, and it has TONS of great reviews. It’s particularly good for dry skin, but is lightweight and works well on oily and combination faces too. There is a body version but I struggled to find anywhere to buy it, annoyingly. There’s nothing stopping you using this all over other than cost though.
Available at: hhttps://amzn.eu/d/57wtyHe

Best Premium Sunscreen: Paula’s Choice Super-Light Wrinkle Defense SPF 30
Again, this mineral-based option is more a face-specific one. It says for combination to oily skin, but honestly it’s great for all skin types. It leaves a really nice matt finish and also aims to reduce the appearance of existing wrinkles too. It is a bit expensive though.
Available at: https://amzn.eu/d/2iLfS6X

Best Next Generation Sunscreen (and if you don’t like mineral sunscreens): Bioderma Photoderm Aquafluide SPF 50+
This is a chemical-based sunscreen, but uses Tinosorb S instead of the more damaging ingredients found in other sunscreens, AND it’s pretty affordable, so definitely a good option if you can’t find a mineral sunscreen you like.
Available at: https://amzn.eu/d/dA2PsOH

Even More Next Generation Alternative (and great for oily skin): Avene Sun Cream SPF 50+
This contains both Tinosorb S and M, as well as their own patented TriAsorB™, which supposedly is even better at UV absorption and minimising harm to marine life. I eventually found its chemical name as Phenylene Bis-Diphenyltriazine, and there actually are studies supporting Avene’s lofty claims, although these are mostly preliminary results. Still, this could be a good (and surprisingly inexpensive) alternative to mineral sunscreens.
Available at: https://amzn.eu/d/3YADsFd

Best Sunscreen for Young Children and Babies: Thinkbaby Sunscreen Baby SPF 50+
This mineral sunscreen has high protection, isn’t too expensive, and has no nano-particles (which could be harmful to young children as well as marine life).
Available at: https://amzn.eu/d/8VxawgS

Note: I am not sponsored or paid in anyway to list these products.

Whatever suncream you end up buying though, just make sure it will actually protect you from the sun. There are plenty of reef-safe options that don’t compromise on effectiveness, like the ones listed above, but some aren’t as good. You’re looking for broad-spectrum UVA and UVB protection, with water resistance and at least 30 SPF; ideally factor 50.

Also do bear in mind differences in skin tone. While I’ve tried to pick out sunscreens that don’t leave a white cast, this may vary depending on your complexion.

Other things to consider

While sunscreen is the main skincare product people tend to think about as potentially harmful to ocean life, I think a lot of people forget about other things like moisturisers and makeup. These also wash off you into the water, and it’s important to do your research into whatever you use to make sure it’s not damaging.

Also, while coral reefs are known for being very vulnerable, other aquatic environments are also susceptible to damage from chemicals in toiletries, including fresh water habitats like lakes and rivers. And don’t forget your own health! This article is focused on reef damage, but there’s evidence to suggest chemicals in sunscreams can be absorbed into the bloodstream. While not necessarily dangerous, it’s worth bearing in mind for long-term use.

And lastly, I’ve tried to cover the main chemicals known or suspected to be damaging, but most toiletries contain tons of ingredients, and it’s hard to weigh up the risks of every single one. A lot of them likely haven’t even been studied much in this context. The safety of some ingredients is also dependent on them being properly processed, and other things like ‘parfum’ or ‘fragrance’ are quite ambiguous, and ultimately it’s not clear just from the ingredients list what they actually are.

Sources

https://pubmed.ncbi.nlm.nih.gov/22276179/
https://www.frontiersin.org/articles/10.3389/fmars.2022.985195/full
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC8002239/
https://www.ncbi.nlm.nih.gov/pmc/articles/PMC7794803/
https://onlinelibrary.wiley.com/doi/full/10.1111/jdv.18196